Around the world, housing prices have been rising faster than many can afford. Rather than accidentally moving into a retirement community, some are intentionally choosing intergenerational living situations. For instance, 27-year-old graduate student Siobhan Ennis is now paying $400 a month (along with some chores) to live in the bottom level of retired physics professor Michael Wortis, who’s old enough to be her great-grandfather.

‘We’ll be friends for life,’ Siobhan Ennis said of her roommate, who is 58 years her senior.

That’s very sweet. But realistically, when talking about an 85-year-old man, that may not mean a whole lot.