Rebonding advice needed

Hello everyone and thank you very much for taking the time to read my rabbit issue. So we have 4 bunnies ( all approaching 1 year in June/July - all neutered in November 2019). 2 half brothers (mini lops) and 2 sisters (double maned lion heads). The males started to get extremely aggressive with each other. To the point where I fear for their safety. We had to take one of the males to the vets as an emergency due to possible GI stasis. It was an emergency so he went alone (I know, mistake number one). So he is now fine but the bond between his brother is gone and also one of the sisters. The older sister is slowly accepting him (1 week so far) but they have an issue over dominance. Both like to be dominant. So my questions relate to whether we should keep pushing the older sister and separated brother. I feel conficted as she has such a good bond with her sister and the other brother and I don't want this risked at all. We have completely separated the younger brother out so happy to try the younger brother with the trio in a month so hopefully all the bad memories of fighting can fade. Any suggestions welcome.

Hi and welcome to the forum :wave: I am sorry that the bond has broken down between your bunnies.

The fact that you took one of the bucks to the vet by himself might have been a factor, but not necessarily so. Sometimes a bond will break down when one of the group is unwell, as it can upset the hierarchy of the group. You have said that you would be willing to keep them separated for a while and then try again and this is what I would do. I think you will need to attempt the re-bonding as though it was an initial bond, with a small, neutral space.

I hope that it works out well.