Buster will be two next week and he has been the same weight for almost a year if not longer. He went to the vet today and he was 4.2 lbs.
The last time he was at the vet he was 3.8 lbs. He fluctuates between those two weights. During his first year, I too, had hoped he would get to 5 lbs. but he has never been close. I will love him no matter what he weighs but he is very fragile. Maggie is 6.2 lbs. and she seems to be a lot "sturdier".