Hi,
I keep my four does in pairs, there weren't big problems when one, or both were bred. Actually, they get along better in these times - feeling better and having a purpose since that itch got scratched, I suppose. My hutches are big enough, actually it's two hutches each, connected by a tunnel, so they can go out of each others sight when in bad mood, and I can divide the hutches so that each has her own for one or max two days (but still spending garden time together) when kindling, not really necessary but makes it easier to make the doe chose the right nestbox.
The second doe always was a good stepmother when the kits left their nest, when both had litters they mixed and it made no difference anymore which kit belonged to which doe.
What didn't work well was when one doe had a litter several weeks after the other :? - the older litter trampled and soiled the new nest, so I needed to keep them away while not separating the does.
Also my buck was always friendly to the kits (does of course separated), it's just when accidentially one from group A meets anybunny from group B, like escaping the hutch when the other fraction has garden time, that conflict erupts, some chasing and tufts of fur flying.
Ah, you didn't tell much about that second bunny you have? It's not an intact male, right? That would be a quite different matter.
How old are your rabbits, and which buck would you use?
May i ask what you are planning to do with the offspring - any chance to sell them in your region? Here, that's pretty much impossible with my mixed breed now, or for any private breeders, thanks to idiots :evil: