Please don’t blame the bunny, as it is completely normal for rabbits to lose litter habits when they start to hit puberty, as well as when they are around rabbits that they aren’t bonded to. You have both of those things happening, so it’s pretty expected in my mind. (I also have the utmost empathy, as I am currently getting ready to attempt to bond a quad and it’s been pee and poop wars for weeks now… I had three buns with great box habits and then the forth bun threw a wrench in the whole situation!) The good news is that once they are bonded and hormones have settled everything should get better.

Also, as an aside, babies cannot truly bond, so it’s possible that fights could start occurring around 12 weeks. Especially with a male in the mix (even though he’s neutered), once the girls hormones start coming in things can start getting heated. I would personally plan to keep them separated until the girls are spayed and you can bond them.

In the mean time, I’ve been using a big sheet of vinyl flooring from the hardware store to protect the floor. Puppy pee pads can be really helpful as well so they aren’t just sitting in pee.

There is also a chance that there could be a medical cause for the girl peeing all over (but I think it’s less likely). Does it seem like she is dribbling urine, or is it large volumes? Dribbling small amounts can indicate a UTI.

I agree that this is less so one rabbit ruining others’ habits, and actually just rabbits approaching puberty and being around other rabbits, thus litter box habits sort of fly out the window. Rabbits mark territory to feel secure, and as they grow older/encounter other rabbits, the instinctual drive to mark follows.

As Dana mentioned, baby rabbits do not truly bond. It can be easier to bond them since they have a history of a good relationship, but a proper bond needs to be established, which baby rabbits do not by default have just by being siblings/being raised together. Rabbits will just as easily try to attack and mate with their parents/siblings. It sounds like perhaps you were lucky in that the original brother and sister you had formed a proper bond, but that may not be the case for the two sisters you newly adopted. For both safety and to guard against pregnancy (in case one of the sisters is mistakenly sexed), I also recommend separating all of them until they have all been spayed/neutered. In the meanwhile, yes, your neutered male may start displaying hormonal behaviors, like marking, even though he is neutered. Is this caused by the other female rabbits? Yes. But it is in reaction to them being there, not because their habits are rubbing off on him.

Thanks for the extra info, but it really doesn’t change my suggestions at all. Spaying and full bonding once everyone is castrated should solve the problem (or at least greatly improve it). Babies and teenagers can be difficult/impossible to litter train, I think you just got pretty lucky with your other bunnies. The puberty timing could be slightly different between the girls, explaining why they are different.

It is really great that the rabbits get along. What I think myself and Dana want to highlight is that baby rabbits easily get along with others since their hormones are not driving their behavior yet, While it’s not guaranteed things will change when hormones begin happening, the likelihood is quite high. There are many topics on this forum and other rabbit forums about “siblings fighting”, which often talk about how everyone got along so well for such a long time, but suddenly, around when we expect puberty to happen, fights begin breaking out. It is something to keep in mind, and the idea of separation is the most cautious approach, as it’s unrealistic to think you can watch them 24/7! Everyone needs to sleep, haha.

In terms of what you’re connecting as a cause, which is the one rabbit peeing which causes the other rabbits to react accordingly, makes sense. Rabbit social and territory dynamics are very scent-based. As such, the solution goes back to doing what you can do reduce the scent and what may be facilitating all the rabbits to mark, and re-mark spots. That is where the emphasis on spaying comes in so that both the sisters’ hormones minimize their hormonal-driven behavior and also so their hormonal presence does not influence your neutered male’s behavior.

From my own experience, which is having one rabbit who is wonderful with litter habits and the other who is terrible (and has been terrible since he was young; just who he is), we never really know what’s happening in a rabbit to make one influence the other. We have grown confident in hormonal-driven reasons since we see the differences between a fixed rabbit and non fixed rabbit again and again. My one rabbit has left plenty of carpet stains, but the other has never seen it as a place to re-mark or seems tempted to do so for whatever other reason.