Papyrus and you were still fast asleep when Sans left to go outside.

He smiled warmly at the sight of his brother who had his arms around you and was snoring softly; you, on the other hand, were as silent as a church mouse with a tiny smile on your face, your small body on the cushion again.
Sans chuckled and walked outside into the cool night air of Snowdin Town.

After a while, Sans crossed the bridge where he first met Frisk (the kiddo now lived with the Dreemurs) and stopped.
Wait...
Toriel was a mom to both Frisk and Asriel and, at one point, Chara.

Maybe he could ask her for advice!

He strode to the vast purple door leading to the ruins.

Perfect, he thought, for practising knock-knock jokes.

But that wasn't the reason he was there.

Well, maybe one wouldn't hurt.

"*Knock knock*" Sans said while rapping on the door.

"Who's there?" came the voice of Toriel.

"Mickeys"

"Mickeys who?"

"Mi-keys are lost so I can't get in" Sans concluded, the sound of amused laughing followed the joke like a shadow.

"Hey, Tori. I gotta question to ask ya" the skeleton admitted, sitting down with his back against the door.

"Oh? what is it, Sans? is everything alright?" Toriel asked, a bit worried.

"Yeah, yeah, everything's fine! it's just....well.....I took in this little baby centaur since I found her alone in Hotland near Alphys' lab. Strange, I know. But, I kinda wanna ask you for advice on...parenting" Sans said.

"Like, what stuff do I need? how do I be the best dad to her?"

Toriel thought for a moment, then opened the door a crack so she could see Sans.

"Sans, are you telling me you desire to be a father to this baby?" Toriel asked, her trademark motherly smile radiating a warm feeling which spread through Sans' bones.

"Uh, yeah. I mean, technically I would be her dad, since, y'know, I took her in and all" Sans replied.

Toriel nodded slightly.

"I can help, if you want, Sans. Just love her and care for her as best you can" she told him, stepping out of the confinements of the ruins, the snow crunching as she walked.

Sans and Toriel headed to the skelebro's house. Sans letting her inside, gesturing to you and Papyrus who was still sleeping next to you.

Toriel smiled warmly once again.

"She's adorable, Sans!" Toriel said gleefully.
As she said this, your innocent E/C eyes opened and looked at her; you tilted your head slightly, a confused "ooh" noise coming out of your mouth.
She giggled at this, Sans smirked.
Payrus opened his eyes.
"Hello, Lady Toriel! Nice to see you again!" he greeted, as chipper as ever. Though he still felt a little weary from being awoken.

"Hello, Papyrus. I heard about the new arrival, so I came to see if I could help you two take care of her......(Y/N), was it?" she asked.
"Wowie! you're great at guessing names and knowing things!" Papyrus chirped.

Toriel smiled.
"Well, don't forget I am a mother myself" she reminded him.

You reached your tiny hand out to her, holding her paw.

They all were in awe at the sight.