Thank you for all the replies.
I will take her to the vet this week and have her checked out.
I suspect she was hurt by whoever abandoned her. Unlike Jeddy (her sister) she is not very affectionate and she shies away when I want to touch her, especially when she comes towards me and I want to rub her head. At night, when she cries outside and I let her in, I have to stand away from the door and then she shoots in past me. If I stand right in front of her she won't come in.
I understand that cats also regulate their own food intake and unlike dogs. won't gobble up all the food in the bowl just because it is there. I notice Jeddy eats little bits at a time but Miss Miley just eats and eats until there is nothing left, and then she will still beg for my food when I am eating. I think it's psychological and a result of being abandoned. She obviously got the worst of it.
Thanks again for all the replies - I am taking them both to get spayed and I will bring all this up with the vet.
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