My brother and his family moved in with Mom when she turned 90. (Thank God for that, and his angel wife!)
Still, my sister and I continued to check on Mom on alternate days just for extra assurance. That also served to check on my brother’s family. I can’t even imagine going weeks without knowing.
(Of course, his children must be pretty old, too, and perhaps they weren’t able.)
My mother is 87 and in a nursing home for memory care. She only remembers my younger sister these days, and she goes to check on mom every day. She says physically she's doing fine but her mind continues to digress. But all us kids are happy to see that she's being checked on and cared for.
My daughter is invested in how I'm doing, what my future plans are, etc. So she's always looking out for me.