I recently gave my 7 years old cat to my brother.....he has had her 3 days now and is telling me she hasn't eaten anything and he doesn't think she is drinking either. He says there is nothing in her litter box to clean up. She has always been a very shy cat, so I thought it would be better for her to be in a single cat household (I have 3 other cats). However, my brother says she is hiding all the time and won't eat even if he brings the food to her. She is a small bodied cat, but a little on the heavy side, so she didn't miss meals when here. What can we do?