When a new cat comes, the old cat’s personality changes because the cat smells a strange smell and feels that the territory and owner have been taken away, so the personality will change drastically. The old cat’s personality will generally become more... Fierce, irritable, difficult to get close to, or depressed, especially male cats, the situation will be more obvious.
Tips:
If the old cat has a drastic change in personality, it is best to separate the two cats and then raise them more Take care of the old cat and let the old cat adapt slowly.