Here is a story my Grandpa Walker used to tell us when we were kids. I just told it to Timo this morning. I hope he believes me as much as I believed my Grandpa. Only when I finally studied Biology did I learn the truth!
When God was making you, and putting you all together, He finally finished His work and took a good look at you. "Hmmm, I think this one needs to be hung up to dry." So He put you up on the line, pinning you there until you were good and dry.
Then, He went along to see all the new babies He had made, testing them to see if they were done yet. And each time one of the kids was 'done' He would take His finger and poke them in the belly, and say, "Yup, you're done!" And the place where He put His finger left a little knot on your belly, and that is how you got your bellybutton!