The nation's first family tree is about to gain a new branch. The future in-laws, it turns out, are not unlike the Bushes. Henry Hager, 29, who was engaged to Jenna Bush, 25, in August, hails from a world of good breeding and foregone conclusions. His parents, who live in the West End of Richmond, are staples of their society. Like the Bushes, with their prominent forebears and their best schools, the Hagers are a Good Family, in the old sense of the phrase. So much about the Hager family reminds you of how things used to be.