Purebred dogs can vary quite a bit from their written breed standard if they aren't being bred with much care to their conformation and type. Even within the same litter. So it's possible that the dogs are purebred - or mostly purebred - boxers. It's also possible that they're mixed with any number of other breeds, or even have no boxer at all! Since there can be multiple fathers to the same litter, it's also possible that one sibling is pure and the other is not, or they're both different mixes. Without pictures, it's hard to say either way, and even with pictures it can be extremely challenging to ID a dog's breed mix.
Bandogges are, to my limited knowledge, mastiff mixes specifically bred for sport and work (protection, estate guardians, hog hunting, etc.). While there are all kinds of breeds that can go into a bandog/bandogge, if there isn't a big demand for that kind of working dog in your area, it's more likely that, if they are mixed, they're just a happy accident of a couple local dogs getting together.
A DNA test is your best bet to know for sure, though. Embark is generally considered the best of the best, though Wisdom Panel isn't bad either.
Bandogges are, to my limited knowledge, mastiff mixes specifically bred for sport and work (protection, estate guardians, hog hunting, etc.). While there are all kinds of breeds that can go into a bandog/bandogge, if there isn't a big demand for that kind of working dog in your area, it's more likely that, if they are mixed, they're just a happy accident of a couple local dogs getting together.
A DNA test is your best bet to know for sure, though. Embark is generally considered the best of the best, though Wisdom Panel isn't bad either.
