Some of my friends with preschool and early-elementary children routinely give their children a snack shortly before bed to help them sleep better. On the other hand, we have generally limited post-dinner eating to a light snack or dessert. We don't particularly notice a problem with our children being too hungry to sleep. (Although they do seem particularly hungry in the morning.)
It occurs to me that some children could be genetically predisposed to needing a full stomach in order to sleep. But it seems more likely that bedtime snack has become a ritual needed that helps relax a child. Some families brush teeth, read a story, or turn on music while others eat some cheese and crackers.
Is there any evidence that food helps children fall asleep and stay asleep?