Children's book about mentally disturbed children in a ward with a cat who lives with them

[Tonia]

Story about a group of mentally ill, disturbed, or foster children in a psychiatric ward or children's shelter and they adopt a cat who lives in the ward with them. The cat comforts this particular child who is the most disturbed and at one point, the cat is on the elevator with the kids. Genre: children's fiction/suspense/adventure. I read this book somewhere between 2004 to 2009.

[Kris]

A guess - The Cat That Was Left Behind by C.S. Adler?

[Tonia]

Kris wrote: "A guess - The Cat That Was Left Behind by C.S. Adler?"

No, I don't think that's it. The boy was part of a group of other mentally ill children, like in a psychiatric ward, not a foster family.

[Lobstergirl, au gratin]

Tonia, are you still looking for this or did you find it?