My mom used to say that your job as a mother, from the time your child is five, is to prepare them to leave home. I always thought that was perfectly sensible, until my own child was inching toward the door. There’s a certain parental pain associated with that bleak phrase: empty nest. I imagine every mother has moments that embody that time. One of mine came when our son was about to graduate from high school. Good friends had a big party for families who had gone through sc