My Grans cat is similar, she got her from a rescue centre.

Sophie (the cat) will hide if anyone new comes in the house, she is really shy.

My Gran then got a new kitten and Sophie got worse, she would constantly hide for days.. so the new kitten went to live at my Aunties house in the end.

Your cat may react differently, but she may see another cat as a threat if she is already so timid.

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