If it's just for family sharing and you're not too fussed about courting for comments or fishing for favourites, then upload whatever you think the family will be interested in. I generally set any family-shared shots to be viewable by family only, and both sides of the family have been set-up with a Flickr account (and most of them do not use Flickr except to view these shots and similar by other family members). Having said that, of late most are now being shared as prints rather than online because the frequency of family get-togethers has increased (a flurry of significant birthdays).
If you were looking to showcase your photography, get specific feedback or to pimp your account for views/favourites/explores then I'd suggest being a lot more selective about what you upload.