One of our cats recently passed away. It was very sudden and unexpected. One of our other cats, Keith, took the death very hard. He was depressed and grieving for several weeks, but slowly came back to himself. Now, one of our other cats has been diagnosed with a serious heart condition - DCM - and the prognosis is not good. She has been very unwell for the past few days. Keith is acting very depressed again. He doesn't want to leave our sick kitty's side. I am keeping our sick girl isolated in our bedroom today just so I can monitor her litterbox use to make sure her heart meds aren't affecting her kidneys. It's only been a couple of hours and Keith is inconsolable. He lays at the door to the bedroom and meows and scratches to be let in. I did let him in for a few minutes so he could see her, but he is just miserable. He has been so depressed this past week. His eating is fine, but no playing. All he wants to do is lay close to our sick girl. Is there anything I can do to help him? I have been trying to give him extra attention, but he seems to be grieving for her even though she is still with us. I myself am heartbroken with the situation, but seeing Keith like this is making it worse. He's normally such an active, silly boy.