I’m pretty sure you’re not supposed to just leave a new bunny in your current bunny/bunnies’ cage until you’ve done at least a few days/weeks of having them separate and doing bonding sessions. You can’t monitor their behavior at night or when you’re not around, so though things might initially look good, you won’t really know until you see their behavior over time and a serious fight could still happen.

The new bunny needs to be housed separately and you need to go through the bonding process. It could be really quick but you still need to go through the process and then do the cementing phase so that you don’t put your bunnies in possible danger.

Someone else who has direct bonding experience might be better able to help you though.

Also, how old is your new bunny? Sometimes, adult bunnies will accept ‘baby’ bunnies just fine but things rapidly change once the baby bunny hits puberty and his hormones start going crazy. That’s another thing to be really careful about.

It’s also important to know if your bunnies are altered (neutered/spayed), so let us know about that too so we can better answer your questions.

I don’t know, obviously it’s your prerogative and I’m glad it’s going so well, but I personally don’t think I’d feel safe housing them together unsupervised so soon after they’ve been introduced, regardless of how well their interaction is going.

I’d want to see them act safely and happily together under my supervision over a few more day’s time before housing them together at night when I’m not there to prevent potential problems.

I would stick to bonding dates for now and take it slowly. Once you feel confident about moving them into the same cage make sure you completely clean the cage (even better if you can move it, rebuild it, etc) so that it feels neutral. Bunnies can get along at first and then start a big fight – I would rather go slowly and know how they’re going to interact before leaving them in the same cage together.