I'm not a Breeder, but I was told Yorkies should really be at least 2 years old before they breed. This came from our Vet who is a Yorkie Breeder and wanted me to know in case I was going to breed Princess. Breeding takes a lot of research. I don't want to upset you in any way, but this is a question you could answer if you did all your research to be a Top Breeder. If you are going to breed your furbaby, I wish you a healthy litter. Please research as much as you can before you breed. If Princess weighed more, (she's almost 5 pounds) I might have let her have a litter, but from what I read, it was best for me to leave the breeding to the Breeders. What ever you decide, I wish you only the best.