The Frog and the Baby

I've heard of many young children thinking they were the ones who were pregnant when their mothers were expecting more children. However, I have to say that I think Nathan is quite confused.
The first time I used the saying "frog in your throat" with him it really took him aback. From then on Brad and I have heard about this frog. It's like his pet. It usually resides in his stomach. For a while he told us it was dead.
Well, last night Nathan was using his inside voice, which meant he was yelling as his form of communication. I remembered a story from a man getting his children to be quiet by saying, "Shh... the baby's sleeping." There was no baby in their house, but who knows, maybe there's a baby at the neighbor's house. It worked. So, last night, I rubbed my belly and whispered, "Shh, Nathan, the baby is sleeping." The rubbed my belly a bit and instantly started whispering back to me. Then he rubbed his belly and said that his baby was sleeping too. I told him he didn't have a baby in his tummy. That was only for mommies. He continued insisting it was true, there was a baby in his tummy, and the more he insisted (at least he insisted quietly) the more Brad recoiled. I told him that mommies had the uterus for babies to grow inside and little boys had penises. Great. So then he said his baby was in his penis.
Brad reminded him about his frog, at which time Nathan said it wasn't a frog in his tummy. It was an alligator.