2 babies were in blanket
1st baby to 2nd baby : Are you baby boy or baby girl?
2nd baby : I don’t know.
1st baby : Wait, I will go in the blanket and tell you.
After some time, 1st baby tells 2nd baby, you are a baby girl and I am a baby boy.
2nd baby : How did you find out?
1st baby : Your socks are “pink” and mine are “blue”.