Crockydoodle, the OP's child does not sound "perfectly ok" at all - and unlike Boo you can't accuse me of not having and thus not knowing about teenagers. One of my 2 is the same age as and sounds very similar in personality to Toughasoldboots' daugher but she has never and would never dare to abuse my pets.
There is yet more solid advice from Salsmum and I really urge the OP to rehome the pets as they are not safe in her home and certainly, as Salsmum says, it would be VERY hard to rehome a dog once he had bitten a child. Many dog rescues won't even take such a dog and would suggest that he should be killed.
PLEASE, VIVA, DON'T LET IT COME TO THAT.
Bluntly, you have already failed the poor dog and committed acts of cruelty yourself by allowing this to happen, particularly every month or so. It's not like it's a one-off! This is not just immoral, it's a criminal offence so if not for the dog's sake then for your own - and potentially your child's as you are allowing her to be at risk of being bitten by your dog - please approach a no kill rescue and give your pets the lives they deserve.
Both Salsmum and I have offered to help. I can't speak for Salsmum but for my part, I work for the dog, not for any particular rescue, not for the owner or the prospective owner and not for myself.