Girardi was born in Springfield, Virginia, a suburb of Washington, D.C., the youngest of four children (two sisters and one brother), and educated in Springfield, Athens, and Paris. "...I went to Catholic school, and she told us stories from the Bible. Then she left, and a Greek woman came and told us Greek myths. So as a narrative, it was the best education that you could get." His father was a CIA agent starting in Vienna, then Athens (during the military coup), and then Paris.