This is a really sad situation, I wish you and your family the best.

These kind of situations are WHY cuddly little baby bunnies are not right for most people... they're sweet enough when they're little, but can develop aggression and/or shyness, and the only instances I've seen of this have been directly related to abusive or neglectful homes (and homes with very rough young kids). NOT saying that this happened to Roxy - it could've even been her previous home. But, just a few scary experiences could have definitely caused her aggression.

Spaying/neutering will not cause aggression, it will definitely subdue it. If a bunny feels secure and content, they will not be aggressive in almost any case.... so, their personalities CAN change. One of my best friends is in Bun rescue, and I've fostered 2. Both of them were super shy and showed some aggression when they first came in, but both totally changed within a week. One of the boys (Munch) I ended up keeping, and he was never a super cuddly bunny but he loved to hop up on my bed and hang out with me and he never once bit or scratched me... even though he came into rescue biting at everyone. Bunnies are seen as much more disposable than dogs and cats, which is sad because they are intelligent and they can be trained. I hope your new boy has a happy life, and I hope Roxy finds a forever home! It's really sad seeing all of your pics of her with sweaters and harnesses on looking so cute, she doesn't APPEAR very mean at all... a really mean Bun wouldn't for a second let anyone put a parka on them.