How can the breeder be an exception when there is no concern for any health testing. or the looks of the dogs that makes them called a boxer?? I know you love your girl, took her in but do you feel she is show quality and should be bred? Look at my dog, I am not tooting my own horn but she has been evaluated, and however is pretty darn close to breedable, but is not, hence why she is on a spay neuter and has been fixed.
People say, well they are not a BYB because they really do care about the dogs. They do this do that etc. Well, that is great but lets put aside the people and lets look at the dog. What gets me is that people regardless of how much they love their dogs are breeding dogs that should not IMO be bred. Just because the dog has the markings of a boxer and its not fixed IMO does not warrent it breedable.
To love a boxer is to appreciate a boxer. To know look at a topline and say damn, that is a straight strong back, to look at a muzzle and admire its correctness. To do that happy dance after the first year and second year holter and get readings of "O" VCPs; to look at the same dog 12 years later and praise the lord that is healthy and has not fallen victim to any heart or health genetic defects. And to call your friends who has their siblings and plan out the next birthday of the double digit club. To see the same dog look at your kids who are now teenagers and remember how you could trust him/her with them at the age of 1 and 4. To me, if a breeder takes some of that into consideration, then heck, nope not a BYB in my book.