I found Nextcloud all in one pretty easy to install, and it's been very stable and simple to keep running. Been up for about a year now.
It's the nextcloud ux that I find kinda frustrating for a family use case. It's got a hundred features you don't want, and the ones you want don't work as well as you'd expect them to. For example, calendar cannot subscribe to external calendars, which is oddly limiting. I don't uses photos, I don't use talk, and I don't use it for mail, presence, messaging, or or most of the other stuff bundled into it. I use files, Collabora office, and notes. And while collabora is reasonably functional on desktop, it's pretty bad on mobile. if she's used to gdocs, and expects something similar, she's probably not gonna like it.