Said It Here

Older cat still hissing at new kitten after months

Even when cats can peacefully stay together in the same space, lingering hissing, growling, and lunging can persist for months without escalating into true aggression. This behavior often stabilizes into a permanent tolerance rather than a close bond, leaving owners questioning whether the cats are simply a bad match or if normal adjustment is still happening.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Giving the older cat high places and personal space to retreat to
  2. 2
    Redirecting the kitten when it gets too annoying
  3. 3
    Using soothing pheromones like Feliway
  4. 4
    Waiting for months or up to a year for them to adjust
  5. 5
    Feeding cats on opposite sides of a closed door
  6. 6
    Holding both cats simultaneously to keep them in proximity
  7. 7
    Using a temporary cat net or baby gate
  8. 8
    Opening the door slightly while blocking it with a heavy object
  9. 9
    Buying more toys
  10. 10
    Separating the cats and doing scent swaps
  11. 11
    Feeding them on opposite sides of a closed door
  12. 12
    Conducting slow, controlled play sessions with treats
  13. 13
    Using plug-in pheromone diffusers
  14. 14
    Giving each cat individual attention and alone time
  15. 15
    Start with scent before face to face meeting by introducing each cat's scent on a piece of clothing separately.
  16. 16
    Keep cats completely separated on the same floor for about two weeks.

In their words

Unedited, most upvoted first, each linked to the thread it came from.

My Persian kitten (6 months, female) seemed really lonely, so I decided to adopt another kitten.source ↗

she and my Persian are NOT getting along at all. They keep fighting.source ↗

My Persian has changed a lot. She never really liked being touched or picked up, but she used to play with us, run around, and be really active. Now she mostly just sits there and eats. She seems genuinely upset and withdrawn.source ↗

It’s been about 4 weeks and I really thought they would eventually bond or at least tolerate each other by now.source ↗

Broad-Fan-6934 · r/cats · 34 upvotes

My apartment doesn't allow me to change stuff and I can't really buy a screen door or something like that at the moment, I have the cage but I feel bad putting one of them into the cage to show them to each other.source ↗

Rc-1138-Boss · r/cats · 20 upvotes

Older cat still hissing/growling at kitten after 2+ months – but they can also peacefully stay together. Will this improve?source ↗

I’m not sure if what I’m seeing is still normal or if these two just aren’t a good match.source ↗

Steppi-Nick · r/cats · 14 upvotes

Olive the OG cat (4yrs) continues to hiss even while they play. She's not bitched up in any way- coat is flat, ears are up, tail is playful. She rarely hissed before he came into the house. Has anyone encountered this before? Is this just the way it is now?source ↗

yarnfrog42 · r/cats · 6 upvotes

My boyfriend’s cat is the same way. When I moved in with my cat, she HATED him. still does, but she can tolerate his presence.source ↗

AirCompetitive464 · r/cats · 1 upvotes

I was told to keep the new one in a separate room but she was meowing the whole time so I left the door open.source ↗

Broad-Fan-6934 · r/cats

Where this came up

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