You were laying down on the changing table as Donnie was changing your diaper cause he wanted to be the first one and so Splinter-Sensei agreed as he kept watch on the two of you, as Donnie was wiping you he noticed something wagging and his eyes widen.
"F-Fa-Father!" Donnie yelled in shock
Master splinter was immediately by his side
"what's wrong my son?" Splinter ask
"Y-Y/n has a t-t-tail.. a t-turtle tail" Donnie stuttered
"what?" Splinter spoke shocked
Splinter looked and seen your tail it was just like a tail of a turtle but it wasn't green it was (Your Skin Color), Splinter put a new diaper on you and held you in his arms as you were falling asleep.
"I'll get to the bottom of this" Donnie stated
"please do" Splinter spoke
Splinter walked to your bedroom that you share with your brothers and he laid you down in a crib he had found earlier, You had crashed and splinter smiled and kissed your head.