Is your 9 year old Doe spayed ? If not bonding with a much younger Doe will be a big challenge, even if the younger Doe is spayed.Even spayed Does can be very territorial, so if your 9 year old is spayed this fact could still be an issue and more likely to occur if the other Rabbit is a much younger Doe.
An older, calm, neutered Buck is the most likely to work out. But there are no guarantees.
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