Food Digestion From a Kid's Perspective

One day my 5 year old told me.....

"Mummy, you bluff me. You said that I will grow big if I eat food but how can I? After I bite the food it all disappears. So how can I grow big?"

I explained to him that when he eats, the food goes into his body and the good things get distributed all over his body and makes him grow big while the bad stuff comes out in his poo.

After a while he said......

"Mummy, I'm thinking that in my body, there are two robots. One robot will catch the good food. The other robot will catch the bad food and throw them on the floor and that comes out in the poo."

Lol. I guess you could put it that way......