My son is 3 and a half months today. He was born weighing 6lbs and 15oz. He now weighs just over 11lbs. My pediatrician said that he is in the 3rd percentile. He eats like crazy, and is exclusively breastfed. The Dr. didn't seem concerned and said that I could try giving him some rice cereal in his milk. How much did everyone's baby weigh around 3.5 months and should I be worried he isn't gaining enough weight?