I’m posting this on a couple different glider sites because I really need some advice.
My three female gliders have lived together for several months without issue, but just recently my latest addition Maisie (who I’ve had for almost a year) has become more aggressive towards Zelda, who I’ve had for two years along with her other sister Brie.

Zelda is literally the most chill and relaxed glider in existence and is a bit chubby. Maisie and Brie are more hyperactive and I noticed a little while ago that Maisie had begun climbing on Zelda’s back. Since Zelda is so chill, she didn’t even put up a fight aside from a couple quiet crabs. I checked her the two times I saw it happen and saw zero marks or wounds. I briefly separated Maisie and then observed her carefully the days after I reintroduced her and didnt see her do it again.

Today when I went to check on them I found a wound on Zelda that was definitely smaller than a dime but looked fairly deep. It wasn’t bleeding but it looked like a literal mini hole on her upper back/neck. I promptly panicked and drove her immediately to the vet where she had to be put under so they could debride and clean the wound. They sewed it up with internal stitches and said since it’s on her back/neck area not to use an e collar.

I will separate her from her sisters until the wound is healed and her hair has grown back, and the vet gave me meloxicam and an antibiotic called clavamox to give her orally. Is there anything else I can do to help her heal? She is an absolute angel and I just want her to get better!

Just for some perspective on how amazingly sweet and gentle Zelda is:
When we brought her to the vet she told us Zelda was the nicest glider she has ever met and the only one who didn’t bite her. Zelda will literally just hang out on my shoulder while I’m at home and chirp happily in my ear. When she met the vet, she immediately climbed up onto her shoulder and just sat there like she does with me. The vet said she was in love lol. If anything happened to her I would be heartbroken. I’m open to any suggestions!

Also, I’m not quite sure what to do when she’s healed. I’m considering separating them permanently, but since there’s three of them I’m not sure how best to do that.

Will a pair do well together?

You can spray the dominance wound twice a day with Veterycin or Mycrocyn spray.

It sounds like the one with the wound is the low man on the totem pole. This could become a regular occurrence.

Brie and Zelda were a pair before Maisie came along without issue. Ideally I would love for them to stay together since they’ve been together the longest.

They can be a pair again once the one with the wound heals up. You don't want the other glider cleaning it as they will make it better.

Yeah I know, she’s separated and will be until her hair grows back and the wound is completely healed. My question is for afterwards. I’m not sure if I should split them up with Zelda and Maisie (the aggressor) apart.

I would take Maisie out as she is the low man on the totem pole.

Maisie is? Even though she’s the one doing the biting? Sorry for all the questions I just want to do this right! :-)

If Maisie is the one leaving wounds on the others she is changing the pecking order in the colony. She is asserting herself.