If you're a parent, you are not - nor will ever be - either childfree (a term that implies having made a choice to not have children) or childless (a term that implies having wanted children but couldn't or didn't and now it's too late). This includes empty-nesters, people whose children unfortunately died, and people who have given up or lost custody of their children.
Angela, I totally agree. I hate it when I hear the phrase, "I used to be CF like you, but then I had kids." No, you were never CF, you were childless. You knew that you were going to have children someday; therefore, you were never CF.
As has been mentioned before, being CF means that you have made a
concious choice never to have children.
