Clear answer · calm next step
My Resident Cat Hates the New Kitten. What Now?
A slower reintroduction plan that protects the resident cat’s routine while teaching both cats that proximity predicts good things.
The short answer
Hissing does not mean the relationship is doomed; it means the introduction is too close or too fast for that moment. Separate the cats, restore the resident cat’s routine, and restart with scent and positive experiences at a distance. Progress is measured by relaxed behavior, not by forcing contact.
Get urgent help if you notice
- Injury, cornering, prolonged pursuit, or a cat too afraid to eat or use the box
- Urine marking, persistent hiding, or rapid weight loss
- Aggression redirected toward people or other animals
- A sudden severe response that may be worsened by pain or illness
This list is not exhaustive. If your cat looks seriously unwell or you feel something is wrong, call a veterinary clinic or emergency service.
What to do next
- 1
Give the newcomer a separate base room with complete resources.
- 2
Exchange bedding or scent cloths without forcing face-to-face contact.
- 3
Pair distant sight or scent exposure with food, play, or calm attention.
- 4
Advance only while both cats can eat, move, and disengage comfortably.
Bring better notes to the vet
A short timeline is more useful than trying to remember everything under pressure. Track these six details: