His apartment felt bigger than usual, emptier too. Although he'd been living alone for a few years now, he'd never really felt the full weight of the place until today. Coming home to a dark, empty house...it just struck him differently, today.

He made dinner for one and just sat at the counter, thinking about the day's events. About people who could lock a child away for having a defect. He doubted the boy even knew that his family had been murdered, and Hyunwoo certainly didn't want to be the one to tell him. In situations like these, the child still tended to have an emotional bond to the abusers, so despite the objective wrongness of their treatment, it was likely that he'd still be upset.

The one benefit he could perceive was that the boy would hopefully be able to use the Yoo family's money to treat his disability. Cochlear implants were expensive, Hyunwoo figured, but if the boy could access the Yoo's financial assets, they would be a distinct possibility.

He wondered what it would be like for the boy to hear possibly the first sound of his life.

He wondered if there would come a day when he and the boy could have a conversation.

--

"Highly unlikely," Dr. Lee said dismissively, and Hyunwoo frowned, looking over at Hoseok.

Hyunwoo had arrived at work only to be intercepted by both of them. Jooheon was taking the boy around the building on a snack trip, which gave them a little time to talk in private.

"You don't think he'll be able to speak? Even if he gets hearing aids or implants?" Hyunwoo asked, feeling the bright sense of possibility deflate from within him.

"I don't mean that he won't be able to communicate in some sense," Dr. Lee said gingerly, taking in Hyunwoo's distress. "It's just that..." He looked over at Hoseok to continue.

"Minhyuk and I were discussing the boy's case," Hoseok said, making direct eye contact with Hyunwoo and smiling empathetically. "There's two main roadblocks. The first is that he was essentially isolated from language for the past thirteen years, so he is experiencing severe language delay. Most children develop the basics of language within the first five years of their lives. After that..." He shrugged a shoulder, his brow furrowing slightly. "There have been several cases of children in similar situations, the most famous one being the case of a girl known as Genie by the psychological community."

Hoseok paused before gesturing for Hyunwoo to sit down, and they each took a seat, Dr. Lee and Hoseok sitting across the table from Hyunwoo. "Genie was severely abused and neglected for the first thirteen years of her life, conditioned into silence," Hoseok continued, looking troubled. "Even though she picked up some vocabulary after being removed from that environment, she was never really able to grasp language structure. She could visually represent things, but she couldn't communicate like you and I are doing right now. And what little language ability she picked up regressed after a certain point. So, the first issue I see is that this boy has already aged out of the developmental period in which he should have acquired language skills."

"And the second issue?" Hyunwoo asked. Last night, it had felt like there were endless possibilities. The boy would receive some sort of aid to assist his hearing, and the world would suddenly be open to him. But that had clearly been naïve of Hyunwoo to believe. "His hearing, right?"

Dr. Lee nodded, taking over from Hoseok. "Correct. The two issues are similar in a way. There are many children who either possess congenital deafness or prelingual deafness who are able to make a great deal of progress with amplification technology, such as hearing aids, or cochlear implants. However, the longer a child has gone without hearing, and therefore the longer a child goes without exposure to language, the less effective these treatment options appear to be. Even if we provided amplification for his hearing, the sudden barrage of noise after thirteen years of silence would be overwhelming and unpleasant. He may not even know what to make of all the sounds he's hearing. And there's still not much evidence to indicate that it would be successful in helping him communicate because, as Hoseok said, he's already aged out of the formative stage necessary to build complex language skills."

"So what are our options?" Hyunwoo asked before realizing that there really was no 'our.' His only role had been to find the boy and bring him to a safe location. What happened to the boy next was not something he had any right or claim to decide. "What can be done to help him?" Hyunwoo rephrased.

"Well, there's two main schools of thought," Hoseok spoke up. "There's oralism – that would focus on trying to teach the boy how to speak as well as read lips – and there's sign language or manualism. The first option isn't really much of an option at all given everything we've discussed, so I think our best bet is to have someone attempt to teach him sign language. And I don't even know if it'll work given that he doesn't seem to have language acquisition skills and sign language is still a language in and of itself with its own grammar and structure, but..."

"But we think there's at least more potential with this option," Dr. Lee interrupted. "Children with hearing disabilities often tend to place more emphasis on visual elements. I believe that might give him a small advantage."

"But we can't guarantee anything," Hoseok stressed after a moment. "Cases like his...they're extremely rare. There's not a lot of literature on the subject."

"I understand," Hyunwoo said with a nod. "Thank you for informing me about all of this."

"Of course," Hoseok answered like he hadn't even considered leaving Hyunwoo out of the loop. "I've already reached out to a professional associate of mine. He teaches ASL, and when I informed him of our case, he said he'd be more than happy to help. He'll be coming by for an hour after work each day to work with the boy."

"So..." Hyunwoo paused, scared to hope. "Child Protective Services isn't coming to pick him up yet, then?"

"Not yet," Hoseok confirmed, and Hyunwoo exhaled as relief flooded through him. "I submitted a detailed explanation of the case, and they're trying to assess their options, but they agreed to let him stay with me for the time being."

Hyunwoo nodded. He wanted to ask how long he'd be allowed to be in the boy's life, but he wasn't sure he was ready for the answer. "You'll still bring him to the station every day?" he asked instead, and Hoseok nodded, giving Hyunwoo a soft smile that told him that Hoseok had Hyunwoo all figured out.

"I'll still bring him to work with me in the meantime. You can see him as often as you like."

Hyunwoo just nodded, not wanting to expose how deeply connected he already felt to a child that would be whisked away at any time. He felt unhealthily attached to him, and it had only been a day. But he'd been the one to lead the boy out of the house, and that had left a large impact on him.

"-all the fruit snacks," Jooheon finished saying as he and the boy walked in, arms laden with brightly colored packages.

"Why are you babbling away? He can't hear you," Dr. Lee said after a moment, not disapproving but rather amused.

"Maybe I'm talking for my own amusement," Jooheon replied as he dumped at least fifteen fruit snack packages on the table. "I find myself rather entertaining."

"They're thinking about bringing in someone to teach him sign language," Hyunwoo said, turning his head to face Jooheon.

"Cool," Jooheon responded, grinning as the boy copied him and dumped all the fruit snacks onto the growing mountain. "Can we learn too? The basics at least?"

Dr. Lee looked surprised at the question, but Hoseok smiled warmly. "I think that would be a great idea. If you're all okay with staying late, perhaps we could sit in on the lessons? If he looks like he's picking ASL up, we can arrange for a translator to accompany him and interpret, but it would be nice if we all knew a little bit ourselves."

"I'd like that," Hyunwoo agreed, and they each nodded.

"Well, I have to get back to work," Jooheon said, and Hyunwoo hesitated before standing up.

"I should join you," he said, pushing in his chair reluctantly.

"I can watch him for now," Hoseok offered, smiling at the boy before looking up at the others. "I don't have any appointments today, so I'll hang out with him here."

"He likes drawing," Hyunwoo said, pulling out a handle of crayons from his coat pocket and setting them on the table. "I need to grab more paper though."

"I'll grab some," Hoseok offered as Dr. Lee got up.

"I've got a special new friend waiting for me in autopsy," he said by way of excuse, wiggling his fingers in a wave. "I'll take another look at the younger Yoo son if I have time."

Hyunwoo waved at Hoseok and the boy before following the others out of the room.

--

Jooheon leaned back against Hyunwoo's desk, holding a piece of paper in his hand.

"Well? Are you going to show me?" Hyunwoo asked, leaning back in his chair and clasping his hands.

"Thinking about it," Jooheon said with a smirk. "But first, the chief made it very clear to me that nobody else is allowed to see this and that he had to use a favor from a friend in the medical field."

"Are we allowed to have whatever this is? We're not in danger of violating HIPAA?" Hyunwoo asked, brow furrowed heavily. He knew from past mistakes that failing to go by the book could result in evidence being thrown out, charges being dropped, or a guilty man going free.

"Because our kiddo is a victim of neglect, we're allowed to request the information. The judge – a friend of the chief's – agreed that we had enough to go on to allow access to his records without signed consent."

Hyunwoo straightened up in his seat. "These are his records?"

"His only record," Jooheon said, smile dropping as he handed over the sheet of paper. "Not altogether that helpful."

US STANDARD REPORT OF FETAL DEATH was written across the top in bold. Every required field was filled in; only one field – the first one – was left glaringly blank.

NAME OF FETUS (optional-at the discretion of the parents)

"Shit," Hyunwoo muttered, dropping the paper and letting it fall onto his desk, obscuring the unorderly layer of scattered papers. "The one thing I want to know, and of course it's impossible."

"Not impossible," Jooheon corrected. "Just...more difficult."

Hyunwoo sighed. He didn't want difficult, not right now. He wanted something to call the boy instead of calling him...well, 'the boy.' He needed a name, and Hyunwoo wasn't ready to just invent one on his own. "His parents still kept him for thirteen years," Hyunwoo said slowly. "They must have had a name for him. Even if it's not on any official documentation, they needed something to call him."

"Okay, well, you can try asking them but I'm fairly sure they wouldn't respond," Jooheon said dryly.

"They wouldn't," Hyunwoo agreed, ignoring the humor because his mind was picking up pace. "But there might be one person who would know."

"Who's that?" Jooheon asked, crossing his arms.

"The only other person who knows that this baby-" He picked up the death certificate, shook it at Jooheon. "-isn't dead."

Jooheon exhaled after a long moment. "So now we have to hunt down a doctor. Great."

--

The death certificate had the name of the attendant and the person completing the report, but there was no way of knowing whether those people were merely administrative or if they had been present at the time. Jooheon tried contacting the hospital but was stonewalled on claims of employee privacy and confidentiality.

"I think we've hit a dead end here. For now at least," Jooheon amended, sensing Hyunwoo's growing frustration.

"Somebody knows this boy isn't dead," Hyunwoo said yet again even though they'd made no progress in the past hour. "We just have to find this guy."

"Could be a girl," Jooheon said.

"I've just got a feeling," Hyunwoo said, sighing as he pushed back from his desk. "I'm going to take a break."

"Fine by me," Jooheon said, stretching his arms above his head. "I'm going to grab a quick bite to eat, maybe check up on the kiddo."

Hyunwoo nodded before heading down to the morgue, knocking on the doorframe to alert Dr. Lee of his arrival.

"Come on in to my humble abode," Dr. Lee called out cheerily, pushing a pair of goggles up onto his forehead.

"How's it going?" Hyunwoo asked. He really didn't want to get a close look at anything down here, but his curiosity led him to notice a fresh cadaver on the closest table.

"That's my new friend Lily," Dr. Lee introduced after catching Hyunwoo's stare. "I found what I needed rather quickly with her, so I had time to look at the Yoo's son. That's why you're here, right? To bug me about the Yoo case?"

Hyunwoo shrugged unapologetically. "More or less...Did you find anything?"

"Remember I told you about their matching scars?" Dr. Lee asked, pulling away from Lily to open a refrigerated unit. He rolled out a metal table upon which laid a body covered by a sheet. Judging from the size of the body, it was clear to Hyunwoo that they were looking at the boy.

Dr. Lee pulled up the bottom half of the sheet to expose the boy's stomach area. Hyunwoo felt queasy, but he leaned forward to see the scar Dr. Lee was gesturing to.

"And the boy we rescued has an identical scar?" Hyunwoo asked, moving back slightly.

Dr. Lee let the sheet fall back down before adjusting it slightly to properly cover the boy's body. "Indeed."

"What does that mean?" Hyunwoo asked, frowning. "Is that evidence of abuse?"

Dr. Lee shook his head. "The scars are too precise for that. They're surgical marks."

"Surgical?" Hyunwoo echoed, looking back at the covered boy and recalling an image of the scar in question. "Someone operated on them? For what purpose?"

"I can't say for certain what precipitated the operation, but my guess would be kidney failure of some sort."

"Kidney failure?" Hyunwoo was starting to feel like a parrot. "You think they both had bad kidneys?"

Dr. Lee shook his head, twisting his lips up slightly. "I don't think they both suffered from kidney failure, although we'd have to run some tests on our new station resident to be sure. I'm proposing that one of the sons had kidney failure. This one, specifically."

"Then why would the other son..." Hyunwoo's voice trailed off before the realization hit him, and he frowned, taking a step back. "You're saying they used the kid's kidney to fix Kihyun? That's some sort of My Sister's Keeper shit."

"All I'm saying is, I suspect that if we took a quick peek, we'd see that the boy upstairs is missing one of his."

Hyunwoo couldn't stop the shiver that ran up his spine. "So, they stow their firstborn away because he's defective-" The word felt ugly in his mouth. "-but then they kept him around for spare parts. That's fucked up." The was a cold anger running in Hyunwoo's blood, one that scared him but couldn't be easily dismissed.

Dr. Lee nodded stiffly. "Maybe that wasn't their intention. And that was the only surgical incision I saw on either of them, so it seems to have been a one-time occurrence."

"Once was too much," Hyunwoo said softly, still feeling the anger pulsing inside of him. It made him even more angry that there would be no justice, that the Yoo family wouldn't have to answer for what they'd done. "You think he was allowed to give consent?"

Dr. Lee frowned down at the body before rolling the table back into the compartment and shutting the door. "We have no way of knowing if he issued his consent without locating the surgeon."

"The surgeon," Hyunwoo echoed before nodding briskly to Dr. Lee. "Thank you for taking another look."

"Of course," Dr. Lee said, looking uncharacteristically troubled. "I'm sorry for the bad news."

"It may have given me an idea," Hyunwoo responded before giving a waving and heading out of the morgue, rubbing his arms as he passed through hallways that were a warm respite from the chill of Dr. Lee's workspace.

--

"If the Yoo's wanted to maximize privacy, then they would have minimized the people who were aware of the kid's existence, right?" Hyunwoo said, appearing right next to Jooheon's desk.

Jooheon nearly choked on his sandwich, as he'd been caught completely off guard. He coughed several times and took a long sip of water before swallowing and turning to face Hyunwoo. "Don't just jump out of nowhere and scare me like that, man, shit-"

"Because the more people that knew, the more likely it was that the secret would get out, right?" Hyunwoo pressed.

Jooheon nodded and shrugged, grabbing another sip of water. "Makes sense. So?"

"So maybe the doctor who faked the death certificate is the same one who operated on the boys."

"Back up – what operation?"

Once Hyunwoo had filled Jooheon in on Dr. Lee's new information, Jooheon leaned back as far as his chair would allow, frowning and setting down the sandwich in favor of tapping a pen against his desk.

"So you think there's a possibility that the doctor we're looking for performed a kidney transplant?"

"I don't know," Hyunwoo said, losing confidence in the idea. "It's unlikely that an obstetrician would be certified to perform that sort of surgery. But if he had the skill and knowledge to do it and the Yoo's were aware of that, wouldn't they have chosen to use his services over an unknown doctor's? Not just as a matter of privacy but as a matter of trust. An unknown doctor who learned of their neglect toward their older son might be compelled to report that information. But the Yoo's would trust a doctor who had already lied on their behalf, wouldn't they?"

"Okay, but how many obstetricians are certified to perform a kidney transplant?" Jooheon asked doubtfully, the pen stilling against the desk.

"I don't know, let me check," Hyunwoo said, turning back to his desk and moving the mouse around to get the monitor to wake up. Once it was up, he logged in and opened a web browser. Obstetricians who also do kidney transplants, he typed into the search engine bar. He got a lot of results on whether or not women could get a kidney transplant while pregnant or how a kidney transplant would affect a pregnancy, but nothing that answered his question.

He did see a search result responding to the question What type of doctor does kidney transplants? When he expanded the answer, though, he saw that the procedure typically involved and entire team of people.

He sighed and gave up, leaning back in his chair. "Another dead end. You apparently need a whole team to perform a kidney transplant, so even if the doctor was involved in both situations, he wouldn't be the only one to know."

"But this is good news, right?" Jooheon asked. "If there had to be a whole team of medical professionals present at the transplant, then that means we've got more potential witnesses."

"Maybe," Hyunwoo agreed reluctantly. "It just feels like we aren't getting anywhere."

"We are," Jooheon said, his voice gentle as though he realized how disheartened Hyunwoo was. "Whether or not we find all the people who allowed this neglect to happen, we still managed to rescue an innocent kid, and we're doing our best to make sure he gets the help he needs."

"But what if it's not enough?" Hyunwoo asked. "What if they bring in a speech pathologist or an ASL instructor, and it doesn't change anything? What if we just got to him too late?"

"How was anybody supposed to know that the Yoo family was keeping an extra child locked in the basement for over a decade?" Jooheon asked softly. "How could we have known that?"

"I don't know but we should have," Hyunwoo argued, jaw clenching as he fought with a wave of different emotions. "There must have been signs that nobody paid attention to. This kid could have been saved a lot earlier, back when we could have really helped him. But now it's too late to fix the damage that's been done."

"At least he's not stuck in a basement anymore," Jooheon said, crossing his arms. "Yeah, we got to him late, but at least we found him at all. And that's only because you had a hunch. All the forensics people who were in the house never even thought to ask why there wasn't an entrance to the basement. If you hadn't noticed something weird about the coat closet, nobody would have found the hidden door. That kid would have never made it out of that room. He would have died in there, Hyunwoo, after starving for days. You're the reason he's alive, so no matter what happens – whether or not we can help him regain the fullest quality of life – you did the best you could to find him when no one else would have even thought to look."

Hyunwoo wanted to say that it wasn't enough, but he could tell by the look on Jooheon's face that he wasn't going to argue any further. Instead, he sighed and did his best to change the subject. "What else can we do on this case?"

Jooheon spun in his chair to face his computer. "Another team of officers are working on the home invasion angle. We've been tasked by the chief to look into the boy's case specifically and to keep it hush hush. So my next plan was to go back and watch all the footage of around the time when the Yoo's first baby was declared dead. Maybe I'll find something in there that didn't show up in the papers. See what you can find out about Yoo Kihyun's kidney transplant – that might've been big enough news for an article."

"All right," Hyunwoo agreed. He headed back to his desk and hoped that this lead wouldn't be another one dead in the water.