From your measurements, his weight is approximately on the 50th percentile for his age which is normal. It is frustrating when your child is a fussy eater. It is good he is getting vitamins daily. Is he drinking milk? You can add ice cream to it as a milkshake (milk, fruit, and ice cream blended) or yogurt smoothies (yogurt, fresh fruit, and frozen fruit) in place of milk so he is getting calories and protein to grow. A new gadget called ‘Yonanas’ turns frozen bananas and fruit into ice cream. I am not advertizing for the product, however, it is a great way to get a child to eat fruit who is a picky eater. They think they are getting ice cream but it is all fruit. You can mix it into regular ice cream, too. Try engaging him in the kitchen more. Have him help you with setting the table. Hopefully this will increase his interest in food. The most important is to relax at meals. If he will not eat a certain food, do not make a fuss over it. Let it go and enjoy the meal. Hoped this helped you.