In the sewers, you were walking around when you sat down and tried not to cry when
??: hey dudes!! We can't leave her here!!
??: Mikey's right! We can't leave her!
??: Master Splinter will understand! Let's bring her!
??: YEAH BOY!!!!!!!
??: MIKEY!!!!!!!!!
??: *softly* yeah boy!!!
At the lair, Master Splinter agreed for you to become their little sister
Donnie: guys! Y/N has 25% of each of our DNA!
Mikey: and?
Donnie: She IS our baby sister!!
All: she is!?
Donnie: yeah!
They smiled and they saw you sleeping on the couch so they picked you up and took you to bed

YOU ARE READING
TMNT Little Sister
Fanfic(Pretend its not April) The turtles find you when you were 4 years old and they took you in as their baby sister. But what happens if they find out you are 25% of their DNA. What happens if Shredder is looking for you and your bros?