LOL!! First of all welcome to YT. There is so much information here and some very knowledgable people.
Your baby is very sweet. Right now is when she will gain most of her weight. Bella gained over a pound in that time and then slowed down. Remember a breeder can only guesstimate a pups adult weight, by looking at the weight of the parents. They can never be sure. She will be a little bigger than 4-5lbs fully grown, I'm sure. There is no way to predict. She is a doll what ever weight she is
