to my MIL (FIL is deceased) to "take care of her" but all he does is use her for money.
He lived in someone else's house for the first 20 years of his marriage (free rent/someone on a mission so he lived in their house) until he finally built his own house - on a lot my in-laws gave him. No one else in the family has gotten a free lot to build a house on....
MIL is a hoarder and burns through her money faster than a meth-head, and the oldest enables and helps her because he gets the scraps. The rest of us just watch and take bets on whether or not she'll have anything left by the time she dies.