Laura Joplin is the younger sister of the rock legend Janis Joplin. Her new book, "Love XX Janis," was inspired by a bundle of letters Laura found of her sister's. This is the first time the letters are published. Laura is six years younger than Janis, and was 21 when Janis died. There's a new episode of the VH1 documentary series "Legends" about Janis Joplin, in which Laura reads some of the letters of her sister.