I guess you have to be direct. Tell him he is OLD and needs to take care of himself or you'll end up putting him in a nasty home after a bit
In this case sharing IS caring. Unlike when people share their horrendous weather.
Same here. We got some cheap 6' bookcases when DW's aunt moved to assisted living a few months ago. She STILL has a bunch of boxes full. Prior house had 7' tall bookcases along the stairs. Already had a bunch of lower stand alone bookcases full.
I have NO idea where we are supposed to put the FULL SET of National Geos that are in MIL's basement when she heads to assisted living whenever that is. She's still fine at 88 but then so was FIL until last summer. Now he has Parkinson's and can barely get from chair to wheelchair in assisted living. He is 96.

Don't tell DH and the kids!!!!

WAY too many people getting sick from Delta.
So unnecessary and likely to force more mandates to keep it from spreading. People will get POed over that but their reluctance to get vaccinated will be the cause.
Moving IS VERY STRESSFUL! Keep centering yourself. Om, om, om
No way I would do an air b&b. You can get insurance to cover any problems on a rental and if you have a management company they have to deal with problem tenants. I'm sure they have insurance as well.
Of course there is the issue of taxes. He doesn't want to sell grandma's house since it isn't a primary residence. Unlike really rich people who manage to pay almost no taxes he'd pay big on that sale. He can sell the current house with no federal tax bite since it has been his primary for at least 3 of the last 5 years. If he DOES move into Grandma's house and keep the current house, sell it in 2 years. If he's going to sell Grandma's house, move into it for 3 years first.
Yes I DO know about that! We sold our old house after renting it out for a few years. Sent a huge amount of money to Uncle Sam and the state.