Hi Kristin,
One of the first things when introducing a new cat to other cats is to use a pheromone product. They may help limit the stress in them but is not meant to be a cure-all. Cats may also exhibit some behaviors like this if they see one of the pack members as prey or a weak link so I would suggest having each one medically checked out but at least the older cat. Your veterinarian might be able to help with some behavior issues but you can also look for a veterinary behaviorist at the American College of Veterinary Behaviorists website.
I hope this was helpful.
Dr. Ryan Llera
Summary
Article Name
What are some tips for introducing a new cat to other cats?
Description
One of the first things when introducing a new cat to other cats is to use a pheromone product. They may help limit the stress in them but is not meant to be a cure-all. Cats may also exhibit some behaviors like this if they see one of the pack members as prey or a weak link.
Author
Dr. Ryan Llera, B.Sc., DVM
Publisher Name
Healthcare for Pets
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