A reader writes:
Call me a bit old fashioned, but I don't think any social grouping that does not involve children can be called a family.
But everyone is part of a family, in that everyone is a child with parents and other relatives somewhere. Until they have children of their own, that is their family - their parents, siblings, aunts, uncles, cousins, in-laws ... as far down the list of relatives as you want to go. But a couple - married or not, gay or straight - is not itself a family. The pair is part of a family - actually a part of two families, both their own parent's family and their partner's family as an in-law.
Wherever there are children being raised, there is a family, and it doesn't matter how unusual the configuration is. I'm still not sure if beagles count, though.
I wonder if anyone else out there would be more likely to consider the childless couples (regardless of the gender mix) a family if they were known to have pets? My husband and I were a couple for four years, but it wasn't until we got our dog that I started thinking of us as a family.