A: You're right that kids go through phases when it comes to eating. Right now it seems that your son loves chocolate drinks, but he might change his mind in a week or two and decide that he never wants another one. It's hard to predict with young children. You're wise to offer your son food first, since wholesome, nutritious food is always the best source of nutrients.
Because you're a stay-at-home mom, there's no doubt that you have a good idea about what your son is eating on a day-to-day basis. It sounds as if your husband, on the other hand, only gets to observe your son's eating behaviors at dinnertime, and that's what's causing him some concern. Help your husband relax a bit by keeping a food journal for your son for a couple of days. Write down everything your son eats while his dad is away. Or consider taking a video or photo of your son eating his cereal at 10:00 in the morning or enjoying his veggies at 2:00 in the afternoon and send the videos to your husband. All this might reassure him a bit.
One of the most important tools for determining if a child is eating enough is the pediatric growth chart. Have your husband take your son to the pediatrician to discuss your son's diet and his progress on the growth chart. The pediatrician can share whether your son is in the normal weight range or whether he's underweight or overweight. If your son's weight is in the normal range, it might make your husband feel a lot better. Just like children, parents go through phases. Once your husband has satisfied himself that all is well with your son's diet, he'll be able to relax a little bit about his eating habits.