Last night I got woken up several times by Kirby and DeeDee fighting. This is the first time this has happened since I've had them. I've never seen them fight, nevermind it being loud enough where I was woken up several times (and I usually sleep like a rock). Each time I woke up to check on them they were separated and I couldn't see anything going on.

Today when I was home I had their pouch on me, and Dee was chattering a lot and doing a bit of hiss/barking. Kirby was fast asleep, but she was looking at me while she was doing it, so I thought maybe she was just chatty with me? This is actually the first time I've seen her do this.

Tonight Kirby won't come out and play and keeps chasing Dee around the cage riding on her back and biting at her neck. Kirby was neutered before he arrived to me in January, otherwise I would think that he was trying to mate with her. He is riding her around the cage, sometimes she seems bothered by it, sometimes she doesn't seem to care. I keep trying to get Kirby off of her but he keeps running right back to her.

And just now Dee went into the pouch and starting chattering and hiss/barking and Kirby went NUTS and ran to her immediately. They're in the pouch currently and she hiss/barks every once in a while.

Does anyone have an idea what is going on? Is DeeDee in heat? Why would Kirby be riding her if he's neutered?

I've never had a female glider before so I don't know what's going on!

Edit: Also, I thought I should ask if this had anything to do with Ollie passing last week? This is behavior I never saw before when Ollie was around?

Unfortunately, fixing the boys only ensures no joeys. But each month when a female goes into heat, the males will be right by her side.
Sometimes the females do tolerate it, since they are in heat,
I guess it all depends on how the male treats the female during this time of whether it will go ok or not.
Out in the wild, a female has joeys maybe twice a year, but caught in a cage,
they can have them 4 times in a year, especially when the males aren't fixed.

Well, good to know. Like I mentioned, this is a new dynamic for me.

Should I be concerned about him injuring her? They both seem OK today...

Also, how will this affect the possibility of getting another glider? I'm not going to any time soon, but I thought about maybe getting another male sometime in the next year. Will that cause any issues?

Kirby, Ollie and DeeDee coexisted amazingly, but I'm guessing she just hit puberty, as this never happened when Ollie was still alive.

They could be trying to re-establish hierarchy. They may not smell Ollie anymore, and trying to figure out who is boss.

Well, after that one night it appeared everything was back to normal.

However, tonight when I went to go check on them, DeeDee has a large wound on the back of her neck.

I set-up my travel cage and stuck Kirby in there and will be taking Dee into the vets tomorrow.

I am feeling exhausted and defeated right now. Kirby was the one who opened up the wound on Ollie's face a couple of times. Once Ollie seemed to be healed finally he was able to move back into the big cage for a month without incident before he got sick and passed.

But now Kirby wounded Dee. I understand that it's either a mating wound or a dominance wound, but is he always going to be like this? Am I always going to be in fear of him attacking Dee or any other gliders I put him with?

I JUST put away the hospital cage from Ollie. Having to pull it out again was heartbreaking.

Kirby also bites me fairly hard, as well, breaking the skin most times. He doesn't nip at my hands, but will bite me in the middle of my back or my chest. I will "psst" at him or distract him with a toy and it doesn't faze him - he just bites harder until I pull him away.

What do I do with this little guy?

Maybe he needs some alone time...

Maybe he will do better as a single glider.

Well, he's going to get some alone time no matter what because I only have the two and they're currently separated.

They've been together for seven months and they never had any issues. Why would something like this happen now?

It's hard to tell. But through my own experience and in reading advise from members helping others here, I have learned that 'time out' gives them a new perspective on their cage mates. Ollie (bless him) may have been the glue that held the colony together.

I'm hoping his solitary confinement will do some good!

I have DeeDee on antibiotics now, and her wound was already scabbed over this morning, which is good. I'm going to pick up some Veterycin today.

I tried to let her and Kirby visit with each other last night, but he immediately went for her wound, so I stuck him back in his cage immediately.