If your measurements are correct, his weight is just below the 25th percentile and his height is above the 95th percentile for his age. As a guideline for a 4-6 month old child should eat the following: Breast-milk or Formula (6-8oz) 4-6 feedings a day. Infant Cereal (1-2 Tbsp) 2 feedings a day. Suggest giving him stained yogurt, cottage cheese, for calcium and protein to supplement the infant formula he is not taking in. Hoped this helped you.