Melissa Gilbert's six-year relationship with ex-boyfriend Rob Lowe was full of ups and downs. "I was such a baby when Rob and I were together," Gilbert, 61, said during a Tuesday, July 29, appearance on Jennie Garth's "I Choose Me" podcast. The former couple were 17 when they started dating in 1981 (Gilbert was still playing Laura Ingalls Wilder on Little House on the Prairie at the time) and they "broke up for the last time" when they were 23 in 1987. "It was very tumultuous," Gilbert explained.