Is it okay to add games my family has, if they don't have accounts here?

[Hephaestos]

if you live in the same house it's fine....

if you live across town, it's just the same as having a good friend and lending games, so not fine at it's really not your collection.

if it's your roomate, that's the same as a friend across town, next year you won't be even in the same appartement...