You'll need to keep them separate until after she has healed from her spay. Often babies will get along with an adult, but it is only temporary. Hormones change all that and one never knows just when those hormones will send either one of them (he could react to her hormones) into a fury. That's why they shouldn't interact until after her spay. You may need a double-barrier (a couple inches between her cage and an ex-pen, for example) to keep them from scratching or biting each other.
Once she's healed, they can finally meet without a barrier between them. Whether or not they decide to get along at that point is totally up to them.
I'm afraid it's really hit or miss when starting with a baby. If your ultimate goal was to find a bondmate for your boy, that is usually better done by having him meet some already-fixed rabbits to pre-screen for potential compatibility. Rabbit rescues do this and then will allow an exchange if a particular rabbit refuses to get along with yours. It's a good way to ensure one winds up with a bond.
