You most likely cannot bond her to him, as her hormones will make it extremely challenging once they emerge. Young rabbits pretty easily get along with other rabbits, making the appearance that all is well, but when hormones hit, the relationship may change. There’s also the possibility that the presence of an unfixed rabbit will make your current rabbit act “hormonally”, even though he’s neutered. I would keep them separated, though I understand that might be difficult.

There’s always a possibility you may be able to, but you need to keep in mind that as she progresses through puberty, the dynamic of the relationship can change and may require you to intervene and separate them to varying degrees.

It’s harder with babies because you don’t know what their personality will be, whereas with adults, you’ll have a better idea of their personality and how it will mesh with you existing rabbit. You should be able to bond then after she’s spayed, but I wouldn’t bother trying until then.

Well there is no need to rush into it if you are having doubts!  I am always a fan of bonded pairs but it is definitely not a decision to undertake lightly! Why not wait a bit and think it over? Proper housing is important during bonding, as even when you don’t need to wait for spaying it can take several weeks (or even a few months in very tough bonds). I am a fan of using x-pens and/or NIC cube grids to make temporary housing that can be reconfigured once the pair is bonded.

Maybe you can adopt an already spayed female  (or neutered male) in the future, then you won’t have to deal with the extended waiting period? If there is a rescue in your area you might even be able to do some speed dating to find a good match. Size, age, breed, or sex don’t really matter, so you might consider other breeds as well. I can’t remember who it is, but there’s a forum member here who has a Flemie bonded with a Netherland Dwarf, and it is the cutest, most ridiculous thing I have ever seen. 🙂

Not sure where the idea that flemies would be better alone would come from… maybe just that they are so big that housing might be tough with two? Or the bonding process might be more intimidating? One of my friends at the rescue I volunteer at has a pair of Continental Giants (Thunderpaws and Stormcloud! :)) and they are soooo amazing to watch together. They are just lovely gentle giants. You have to rub your eyes to make sure you are seeing them correctly because they are so huge!