It's been a few months now since Sans had found you and took you in. And Sans has started to teach you how to walk. Right now you and Sans are in the living room practicing right now. He is across the living room from you.
"alright kiddo,walk to dad." You tried to get up on your feet but fell on your butt. You tried a few more times and finally got yourself to stand up straight for a few seconds before you lost balance. Sans used his blue magic to hold you in your standing position. After a few minutes you gave signals that you wanted to try and he released the blue magic. Your few steps were wobbly and you fell down. You got up and tried one more time and you made it to sans.
" i'm so proud of you kiddo!"
He hugged you and planted a kiss on your cheek. You giggled and he put you down. You kept practicing the rest of the day. Sans was watching tv while you kept trying. Occasionally you would fall forward, but sans would use his magic and catch you before you literally face plant.
*TIME SKIP*
Papyrus has arrived back home from his patrol and was greeted by you running up to him and hugging his leg.
"HAS (Y/N) FINALLY LEARNED TO WALK!?"
"ya, she's been practicing all day. she seems to have gotten the hang of it."
"WOWIE,GOOD JOB (Y/N)!"
Papyrus picked you up and hugged your small figure. He put you down and and you walked over to your dad. You got on his lap and you fell asleep.
"I SWEAR SANS, SHE'S JUST LIKE YOU SOMETIMES."
Sans looked at your tiny figure and chuckled. Papyrus went to the kitchen to cook some spaghetti for the three of you.