Originally Posted by Aki
The size of the rabbits isn't a problem. The doe is likely to be the dominant one - I currently have a tiny blind quite old Nethie girl with a young male lop twice her size and she's totally the boss (rabbits' warren are matriarchies - females being top rabbits is completely normal).
On the other hand, I wouldn't put a male with an intact doe. Even neutered, he WILL try to mount her if she has hormones still (I call that phantom hormones ^^). I made that error when I first got rabbits. The male only stopped bothering the doe and trying to mount when she had been spayed too.
Considering that you would have to separate them anyway when you'll spay her (which will take you to square one in the bonding process), and since your doe is not in great shape, I would wait until both of them are neutered and healed before trying to bond them.
Of course, you'll need to wait until she has gained some weight before spaying her, but she's at an age when she can already have tumors linked to hormones. So it's better not to wait too much before doing it...
I was going to wait until March. Only because I can afford to only do him in January, a month for him to recover, then get her done in March.