Children change their minds about the foods they will eat. Children may love a food, then not eat it for months. Or they may eat it some days but not others. They may eat an enormous breakfast and snack, then very little the rest of the day. They may eat only one or two food items at a meal.
Children are erratic eaters because they are very sensitive to their hunger and appetite.
They will even stop in the middle of a bowl of ice cream if they get full. Children know how much they need to eat. Every child grows differently and every child needs a different amount of food. Some days children are hungry and some days they aren't. Some days they are active and some days they aren't.