Inherited Cat

We inherited a cat yesterday. She was dropped off at our church (I'm assuming) about a week or two ago. Our Pastor has fed her on the days he was there, so she kind of stuck around. She is a Calley-co cat: brown, black, and white, and has long fur. She stayed at the Church and no one would claim her or take her home. She looked so pitiful. Although her hair made her look healthy, she was practically starving. She is so skinny.
We don't have a name picked out yet. We're not even sure if we can even keep her. She makes our other pets really nervous, because she's new and different. Mom thinks we should find her a new home. I would like to keep her, but at the same time, we don't need anymore animals, especially a cat. I feel guilty because I'm the one that talked Mom into taking her home. Now, I think she regrets it...because of our other animals don't like the idea of something new.
She is really beautiful and loving. On our drive home she sat on my lap and didn't really fidget. She liked the love and attention she was getting from all of us. She is calm and friendly.
I really like her and wish she would feel comfortable around our other animals.