Daddy Grew What?!

Some of the things little kids come up with are just so strange!

He just told me that when he was 'born' in his mommy's tummy, he grew bigger and bigger. Then he added, "And when Daddy was born in MY tummy, he grew bigger and bigger and BIGGER. He grew bigger than me. And he grew a big butt, lots and lots of inches. Then he exploded me and he came out of my tummy."

I have no problem with him thinking he could have had a baby, no problem that he doesn't understand he couldn't have had daddy as a baby, he'll figure all that out. What I don't get is why he thinks daddy grew a big butt! What?! His dad is slim, Cody X even says his dad is not fat so where did that even COME from? Little kids steal your sanity because they don't have any of their own to work with...