I just got my male boxer (MAX) 4 weeks ago. He was the shortest of the litter, not by much, but also the stockiest. In the four weeks I have had him he has only gained 4-5 pounds and is hardly any taller. I know it has only been four weeks but I have seen 2 of his siblings just recently and they are much taller. Could something be wrong with him? He eats prettty well (3- 3 1/2 cups per day of science diet). Should I feed him something else? I feed him 3 times per day. Thanks.