Of course, I really don't have any idea of your family dynamics nor needs, but I think about these things sometimes as issues we may need to one day face with our own aging parents, and it brings to mind jlcollinsnh's cautionary tale.
I realize his situation is different from what you're describing, but it's a reminder that what makes sense financially may have other consequences. In particular for him, the psychological factors discovered after buying a condo for his mother and subsidizing her rent:
Now here’s where the psychology gets really interesting. My mother was a smart woman. She understood intellectually that I was supporting her to the tune of hundreds of dollars each month, thousands each year. But she never saw that money. What she saw, and felt emotionally, was the $300 check she wrote and mailed to me each month. Wrote and mailed to (cue me twirling one end of my imaginary handlebar mustache) her landlord.
Meanwhile, when my sisters would visit once or twice a year, they’d slip her $100 to “help with the extras.” A kind and generous gesture that she very much felt emotionally. And, of course, when I’d visit I would get to hear in detail just how kind and generous my sisters were and what a blessing in a mother’s life such children are.