Breeding DDBs

Question
I have two French Mastiff's, one female and one male. The male is about 6 weeks older than the female and I think they probably have the same father and different mothers.If they mated would this produce unhealthy puppies. I guess that would make them half brother and sister if they have the same dad. We got them from a pet store (I now regret that, have recently learned about puppy mills and pet stores.)Thank you for taking time to answer this question......qf

Answer
Hi. I mean no offense here, but I wouldn't suggest to anyone to breed a pet store dog. Because, you very rarely will know the dog's history, their parents, aunts, uncles, cousins, siblings, and what the health and temperaments are. Brother to sister breeding is the strongest type of inbreeding there is. If this type of breeding is to be done, then the person really needs to know a lot of what is behind the dogs. Inbreeding brings out the best and worst, you really need to know what health problems, temperaments their ancestors have. If you were wanting to breed this breed, I would suggest finding a great breeder, and have them mentor you and get you started on the right foot. Good luck!