Wings

I can't remember exactly how this all started, but this is close enough....
A few nights ago we read Eric Carle's "The Very Hungry Caterpillar" to Hudson for his bedtime story. Shortly after, he was eating a lot of junk food and we told him he might turn into a butterfly like the caterpillar did after he ate a lot of junk food.
Now just about every time he eats (or wants to get out of eating is more like it) he says, "I don't want to turn into a butterfly". Or, "I'm gonna get wings and turn into a butterfly if I eat", or something to that effect. It's pretty funny.

How long do I let him go on thinking this? I think forever.