My (17m) dog is in danger of being put to sleep after he bit someone

I have a five year old German Shepard dog, he’s well behaved, trained, and well looked after. He is also very protective of his family.<br><br>Yesterday, my aunt and uncle came to visit and brought along their three year old daughter, she is known to hit and grab dogs. While there, she pulled my dogs ear until it started bleeding, I managed to pull her off him but he then bit her in the back of the head. She has serious injuries and I am probably going to have to put him to sleep after.<br><br>I am heartbroken and I don’t know what to do. My family and I are in a situation where it looks like my dog is going to have to be put to sleep. I know it isn’t his fault, it was a reaction to being in pain, but I’m still going to lose him.<br><br>I’ve tried talking my aunt and uncle out of this to no avail and I desperately need help. The only people who have agreed to let him live are my mum and dad.<br><br>What can I do?<br><br>Edit - I just want to say thank you to everyone for their kind comments, good idea’s and all the support. I will update once I have some news<br><br>Update - They agreed to not say anything to animal control so long as I pay for the medical bills, it’s more than I can afford but thankfully my girlfriend is willing to use her savings to cover the rest. My dog is safe and my cousins ok, I’m just in debt now but that’s not important