It sounds like you are making good progress! No fights + grooming and flopping means you are on the right track. But, I agree with others that more time is needed.
The more time they spend together without aggression, the more Herbert will trust Percy.
Wait until Herbert is relaxed around Percy. When bunnies are finally bonded, it’s like something “clicks” and they can climb all over each other without fear. So if you notice Herbert “flinches” or is tense when Percy comes near, they aren’t ready to move to the next step yet and just need more time.
Once they do reach that point, don’t immediately move to less neutral territory. You’ll want to let that dynamic “cement” for 24 – 48 hours. If it took a long time to get to that point, I would cement for longer… So, if it takes 48 hrs for them to be relaxed around each other, then wait another 48 to cement that behavior before taking the next step.
We’ll be cheering you from the sidelines! I’m prob going to start marathoning mine next week…. gotta stock up on snacks and get comfy sleeping on the floor!
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The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.