You are Kakashi's adopted son, at first Kakashi saw you in the box in the pouring rain when you were a baby and you still looked like a newborn, because Kakashi didn't know who Your parents being Kakashi just decided to adopt him

You're at Kakashi's house right now, and Kakashi is trying to fit your clothes and diapers

Kakashi:sighs"alright it's a bit hard for that, now I'll get you some milk so you stay here okay Little baby"