Letters written by the late columnist Ann Landers to her daughter Margo Howard over more than 40 years, until her death this summer, will be edited and published by Howard in a book signed for Warner. It was AOL Time Warner Book Group chairman Larry Kirshbaum, who knew Howard in high school and had long discussed such a book, who signed it for world rights. The agent was Bob Barnett at Williams & Connolly in Washington, D.C., and Warner plans to publish in fall 2003. The collection, tentatively called A Life in Letters, will contain Landers's observations on her family, including her equally famous twin sister, Abigail Van Buren, author of the "Dear Abby" column, scores of her celebrated friends and current events.