Friend of Felines and Feline Health

Dear fellow paws & whiskers admirers, I have 6.5 cats (one is not really mine). All are rescues, and I've nursed and rescued many litters, from as early as  ~10 days. Rescued a blue-crem torti, 2006 from Smith Beach. Spayed, vac, etc.. Has always been heavy, but lost weight, where her huanches show, but she is eating fine; actually, repeatedly thru the day, thou a bit at a time. All cats (3 manx 2012, brought up from 4wks), others normal weight. I have had them strongid wormed. Why has she gone from ~14lbs to ~7, and will not gain. Note: She had a virus at 12months (she's a bit slow), and spent 6 days 125ft in a popular tree. Had to hire a tree climber. But would that have affect kidneys?      Environ. Biologist.  Peace

Of course being up in a tree for that long could affect many things.  How long ago did that happen?  Has she been taken to a vet for a check up about the weight loss?