The song speaks of the narrator's wish that she could have known more about her father, a traveling salesman who met her mother and quickly married her (the lyrics indicate that the quick marriage was more of an elopement than a shotgun marriage, since "Grandma Kate" – the narrator's grandmother who raised her mother to be a proper lady – likely would not have approved of the relationship).
Unlike other songs where the father is absent due to abandonment, in this song the father died of illness when she was only five.