Plot
About a week in when the brothers found Lillie, she keeps a secret from them that neither of them know until one night, the child can't sleep so she explores the lair until she finds a certain Soft Shell up and awake, deciding to put her well-kept secret with Donnie.

It was a cloudless night in New York and it was pretty calm for the time being, almost all three brothers were fast asleep in their rooms as Lillie was fast asleep in a bedroom the brothers had set up for her, Lillie however started to move in her sleep and she gave a quiet whine as she eventually woke up.

Lillie sat up and looked over at the plushies on her bed, some were teddy bears, bunnies or other cute plush animals that Raph had given her, Lillie then pressed a button on a remote on her bed, activating the fairy lights which were lit with gentle pink coloration, each brother had used something for the room to make Lillie comfortable.

Raph had given Lillie plushies and even a few star shaped pillows to make the kid more comfortable in her bed, Mikey had given Lillie some of his old art supplies like crayons, colored pencils, watercolors and even a new sketchbook for her.

Leo had gotten the kid some cute unicorn slippers, new outfits to wear and even got her pajama onesies so they'd match while Donnie had installed the fairy lights in the room and even made sure Lillie had a nightlight in her room so she didn't feel scared of the darkness.

Lillie climbed down from her bed as she then put her slippers on and she grabbed her plush bunny, leaving her room as she got a bit scared of the dark outside her room but looked up to the stairs leading to Donnie's lab, seeing gentle purple light coming from it.

Lillie then made her way to the lab and she tried to be as quiet as possible as not to wake the brothers up and not interrupt Donnie if he was busy. When she made it to the lab, she quietly peeked her head into the laboratory.

Donnie was fixing up his battle shell which left his soft shell exposed and he couldn't sleep that night so he figured he may as well get some work done, he had his goggles over his eyes as he gave a small but light hum as he continued to work.

He didn't hear the child however as Lillie was carefully walking into the lab, she flinched a little when she heard the purple masked turtle's voice however.

"Leo, for the last time. I am not sharing my energy dr-" Donnie started, he turned around in his gaming chair but he was certainly surprised to see that it wasn't his twin but rather Lillie, he moved his goggles out of his face. "Oh, Lillie it's you. My apologies, I thought it was Nardo. He's more of an insomniac than me.." Donnie mumbled the last part.

"Why are you up?" Lillie asked, she walked over to him and she stood on her tip toes to see what he was working on, seeing the battle shell on the desk/workbench.

"My battle shell, unfortunately it was damaged after tonight's patrol. Luckily it wasn't too severe. What about you? Why aren't you sleeping?" Donnie asked, arching a painted brow at the kid who flinched as Donnie saw this however.

"Nightmare.." Lillie sighed, she was lying as she knew that it was wrong and she gave a squeak when she saw Donnie get up from his seat, approaching her.

"You're lying, you don't do that very often do you?" Donnie asked, he then saw the kid visibly shaking slightly and his gaze softened a bit.

"N.. No.. I'm sorry.. I'm sorry.." Lillie sniffled a bit and Donnie got a bit surprised as he didn't expect the kid to start crying and he crouched down to her height, he was rather hesitant but put a hand on Lillie's head.

He tried to think of what Mikey would do in this situation before an idea came to mind, he had to be out of his comfort zone for this one. "Lillie, do you want to talk about it? It may put you more at ease if you explain why you lied.." Donnie said.

Lillie looked at the soft shell before she looked down at the floor, giving him a nod as she hugged her bunny plushy. "It wasn't a nightmare.. I'm scared, they're gonna come back and hurt me again." Lillie said.

"Who's they?" Donnie asked, looking at Lillie and he moved his hand back as he looked at the orange eyed child.

"The Purple Dragons." Lillie said, she wiped a few tears from her cheeks and Donnie's eyes widened in shock and surprise. "You were apart of their group? But, you're too young for that.." Donnie said.

"I didn't do the coding stuff like they did, whenever we would go out, they'd send me into stores late at night. They tell me that it was all a game, if I found them the pieces needed for their work, I'd win.." Lillie explained, Donnie used one hand to cover his mouth as he couldn't believe what he was hearing.

"Lillie, listen to me carefully." Donnie said, he took a breath and he put his hands on her shoulders as Lillie had a bit of worry on her face. "Donnie.. you're scaring me.." Lillie said.

"Lillie, what the Purple Dragons did was wrong. The game they made you play, it wasn't a game. They made you steal parts for them, they used you. They manipulated you, remember when me and my brothers found you?" Donnie asked, he moved one hand away from her shoulder and saw the child nod in response.

"Well, we caught the Dragons in the act, they left you behind.. as a diversion." Donnie stated, Lillie started to get teary eyed again and she whimpered a little.

Donnie sighed mentally and hated telling the kid the truth but he had to, he decided to take another leap out of his comfort zone and he pulled Lillie into a hug, softly rubbing the girl's head to calm her down.

"It's okay Lillie, I'm right here. You know you're not alone anymore, me and my brothers are here for you." Donnie said softly, he was never this open with his emotions before but he was willing to try for the little one as he heard Lillie start to cry and he hushed her softly.

"It's okay, you're okay.. I'm not going anywhere. The Purple Dragons won't hurt anyone, they won't hurt you ever again." Donnie said, he softly let her go and looked at her as Lillie wiped her eyes and she looked at the soft shell.

"Promise..?" Lillie asked, Donnie felt a small smile tug at his lips but he nodded and made an 'X' over his plastron where his heart was. "Cross my heart." Donnie stated.

Lillie smiled a little and she then felt sleepiness washing over her as she gave a sleepy yawn, rubbing her eyes. "C'mon, let's get you back to bed." Donnie said, he picked up Lillie and carried the child in his arms as he noticed Lillie softly holding onto him while she was drifting off to dreamland.

Donnie went to his room once he had shut the lights off in the lab, deciding to finish up the battle shell in the morning and he yawned a bit himself. He put Lillie in his bed as he took his mask off, setting it aside as he then laid down in the bed too.

Donnie closed his eyes for a moment and he sighed gently before he felt something near him, opening one eye as he saw Lillie nuzzle up to his side and Donnie smiled a little before he closed his eyes again and he put an arm around Lillie to make the child feel more safe and in content.

"Good Night, Lillie."