I don’t think there’s a definitively “right” answer here. She has lived a long life. She has dealt with loss before, and probably knows how to. Yeah, it will probably bring her down a lot, but I feel like being dishonest about something like that is worse. The only way I could see not telling her is if she has something like dementia, and doesn’t remember, for sure, that the cat is there. Imo it’ll be so much worse wondering where it is than knowing.

I have heard of people giving their elderly relatives “robot pets”. Some of them are pretty realistic, and that may be an easy way to give her back a companion, without the downsides. I just googled “robot pet for elderly” and a bunch came up. Obviously, this doesn’t take away the loss of a real live pet, but maybe it’ll soften the blow?

Idk I’m just rambling now.