Dog etiquette - is this rude?

I am in my twenties, living with my boyfriend - we are not married. Since we just moved into a new place, we have wanted to invite friends and family over to visit, but the problem seems to lie with my boyfriend's sister. She has two dogs, which are not very well-behaved at all. They are both extremely attached to the sister to the point of being neurotic. They won't even go near another human being without acting scared or running away. They also have not learned to go to the bathroom outside, and often have accidents inside the house. She tends to blame the dog and doesn't understand why they "don't get it," but I know it is because the dogs don't receive proper discipline and training (hence the reason both of them are so neurotic). My boyfriend has mentioned to her that we would like to have her and her husband over for dinner one night, and she agreed, but followed with a comment such as "sure, us and the dogs would love to come visit!" Now I personally find this to be extremely rude. We have just moved into a brand new condo, with brand new carpets. We never invited the dogs - just the two of them. How do I resolve this? I do want to have the sister and her husband over for dinner, but it seems they won't come without the dogs. I think it is incredibly rude to just ume your misbehaving dogs are welcome in someone else's place without an invitation, but I don't want to cause bad feelings with the family. What do you think?