Most of the time, our kids bring their own lunch boxes with food that’s compatible with our Paleolithic ketogenic diet. Occasionally, they’re allowed to have a slice of the pizza served at the party, but that means they can’t have any more (regular) pizza for the rest of the month. In other words, if we have a pizza night planned on Sunday and they have a slice of pizza at a birthday party on Friday, they’ll have to eat something else on Sunday. I explain the rationale behind all this in my article on how to get kids to eat healthy.