As Nubees, it's only a matter of time before they run into major problems. So, as soon as they can (IMNHO), I recommend they develop a bootable backup scheme with SuperDuper or CCC and have DiskWarrior (or TTP) installed (on more than one volume).

Harv
27" i7 iMac (10.13.6), iPhone Xs Max (12.1)

Those who can make you believe absurdities can make you commit atrocities. ~Voltaire