Anyone have experience with this? Just wondering as I had to let my 14 yr old Misty go due to her having a mass on her lung about 3 weeks ago and her sister of 13 yrs is for sure showing signs of grieving. A lot of things that aren't typical behavior... meowing in the hallway likes she's calling for her, constantly looking in the bedroom for her, sleeping in areas of the bedroom her sister was laying when she was sick towards the end, always looking down the hallway when she comes into the kitchen for her wet food and snacks as if expecting her sister to come trotting to get hers etc etc.