It's Happening Again

I don't know if I can do this again. Easton is approaching the trouble age. My anxiety is increasing. But I'm doing everything right. He's on a hypoallergenic formula. He's not getting milk or soy. His sugar intake is minimal. His foods are healthy. What more can I do. I'm doing everything RIGHT and he is still getting sick. His weight is starting to drop from his growth chart. He was in a nice little cluster there for a while. We could explain why he wasn't gaining as quickly as other kids. For 6 months he was having constant ear/sinus infections. He was gaining just slowly, but consistently growing. He is getting taller so something is going right. But his weight is going no where quickly. At his 12 month appointment I was so excited. He was 20lbs and 14oz. He was getting up there. It looked like we were on our way up. He was over the weight hump. My heart dropped when he got weighed today and he was 20lbs 4 oz. When his doctor looked at his growth chart his dot was no longer in his little cluster but lonely and far below. My nerves are shot I find myself going back to an emotional place I thought I would never have to go again. I have tried to control this situation. I did everything I knew how to do. I've controled his diet so well. the poor kid has never tasted ice cream or gotten to eat a real piece of cake. He is probably the healthiest 13 month old around...He gets excited for veggies....I am at a loss of what else to do. I've done everything I know how to do. I've controled everything I can. But it's not enough. My child is still sick. WHY? WHY? WHY?