My friend's little boy put on weight really fast and was really chubby with rolls (which are soooo adorable) and he was fully BF also.... just fab milk I reckon. On the flipside, at least you don't have doubts in your mind about if you're producing enough etc etc etc. I love rolls on babies, they are just way too cute. Most bubs will lose it and slow down and slim down as they get older... my friend's little boy is almost 4 now and slimmed heaps! He's tall but so is his dad. His dad is also very solidly built so there were some genetics. I say he's all perfect your little man