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Why is my cat losing weight and acting timid after getting a kitten?

Updated On September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | 11 months and 8 days old

Hi there! I've recently noticed a change in my cat's behaviour and weight and I'm getting worried. We first noticed her change in behaviour when we got our kitten Louie. She got timid, quiet and will not play. Just yesterday, I noticed that she's gotten skinnier. I'm not sure if this is because we got Louie at a very young age and now he is growing or she is simply not eating. I would really like to know why Luna is behaving like this and what we can do to get her back to her old playful self.

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on January 16th, 2018

It is concerning that Luna has had a change in behavior and has lost weight. While it can take time for a cat to adjust to a new member of a household, it's an extreme reaction to lose weight. I would be concerned that she may have an medical illness causing her change in behavior. Lethargy and anorexia are unfortunately very general signs of illness and can be caused by systemic illness, infection, inflammation, or injury. I'd recommend a visit to the vet this weekend. The vet can diagnose if there is medical cause behind these symptoms, and can discuss treatment with you if there is one. Good luck, I hope this helps!

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