"A social unit composed of a mother, a father, and their children (at least one)."
Seeing it's current use it's description is rather unfitting. I propose we change it to simply be a ''super-tag'' for any family formation as that seems to be what it's used for by basically any poster.
We could perhaps use ''household'' for what it's currently described as being, which would be more logical seeing as one of the definitions of family itself also extents to cousins, uncles, aunts nephews and nieces.
Of course re-tagging existing images would be a **** in that case... but so would removing all the family tagged images from the ''family'' pool that don't fit the description. However simply changing it to a tag for ''any ( direct ) family connection'' solves that problem. ''households'' are easy to find by searching ''mother_and_daughter father_and_daughter" or ''mother_and_son father_and_son'' as it is, if properly tagged that is.