We have 2 cats 1 male & 1 female 8 months old now. Both are siblings and they were very attached to one another as we separated them from mom when they were only 2 months old. I recently neutered my female cat around 15 days back. In the whole process of neutering we kept both cats in separate rooms. Now my male cat is attacking female cat. What would be the reason? we r still using medicine on female cats stitches, does that smell is the reason for attacking male cat? Please let me know how to solve this problem.

We have 2 cats - one male and one female, which are 8 months old now. Both are siblings and they were very attached to each other as we separated them from mom when they were only 2 months old. 

I recently neutered my female cat around 15 days ago. In the whole process of neutering, we kept both cats in separate rooms. Now my male cat is attacking female cat. What would be the reason?

We are still using medicine on female cats stitches, could that smell be what's provoking male cat's attacks? 

Please let me know how to solve this problem.