Just to add to the confusion....

My vet told me that if I wasn't planning to breed my females to do it prior to their first heat too. He did it at 5 months. That was the minimum age for a female. I don't know about males, but I have heard 6 months for them. My mom just had her little Boston Terrier, Mr. Darcy, "fixed", and he is probably closer to 8 months old.

Good luck, Bailey. And good luck to Bella too!!!

Logan