Am I overreacting?

How would you react if your boyfriends family says they accept your child (that has been in their lives since day one) but then makes comments about “getting their first grandchild”? I know my child isn’t biologically my boyfriends, but he raises her as his own. They call themselves my child’s grandparents yet make comments when they get “real” grandchildren. How do I protect my child from this? Or am I just overreacting?