Hi, Kat.
My best recommendation is to go to the Bonding section in the Bunny Info. section of the site that’s linked in the blue banner at the top of this page. I would also scan some of the bonding posts for similar questions so you can get a lot of info. to start with on your bonding of 2 females. I want to ask if they are both spayed, and are you certain they are both female if not? It’s easy even for a vet to get it wrong, and if you haven’t had one of them spayed or neutered, it’s important to take care of that first while keeping them separate just in case.

That said, the bunnies will do a sort of fighting type dance to decide who is going to be dominant. You want to be nearby when they are together in case a fight breaks out, but otherwise let them go through these stages together as they establish the nature of their relationship. Shedding is OK, though often makes a girl cranky. If tufts of fur is being pulled out by the other one, though, that’s cause for concern.

I am going to move your post to the Bonding section of the Forums, too.

Definitely wait until they are both spayed, it helps a ton!

I doubt that. I have seen rabbits 8 and older spayed at the humane society I volunteer at. Bonding just isn’t possible with hormones around at all. It makes them more aggressive and territorial. I wouldn’t chance the injuries and vet bills due to not being spayed.

I would absolutely spay Chloe and then I would see how things progress from there. Generally, you want all the bunnies involved to be spayed, but I do understand how you feel about Thumper being 8 and your concerns for an invasive surgery right now. Chloe should be ready for spaying within the next month. I would contact the vet and see if you can schedule that.