New Kitty in the house problem

My son has a 3 year old female calico cat. Last week he and his wife adopted a 1 yr. old female

calico to be a companion to the older cat. Both cats have been spayed. The cats have
been kept mostly in separate parts of the house.

They give the cats treats when they
are together. But the younger cat has started chasing the older cat and backed her
into a corner this morning and hit her. Now the older cat is afraid of the younger cat.
What can they do to help them become friends?

Reply
Have they tried the introduction method whereby they are introduced to each other slowly over time? the process is described here
https://www.our-happy-cat.com/introducing-cats.html
Time will tell if they become good friends of not. With cats it is not always guaranteed.

Kate

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