Country singer Emma Jacob's mother died Wednesday night (March 2) at a Nashville nightclub while her daughter was performing onstage during Country Radio Seminar, Country Aircheck reports. Linda Chapman, 55, died instantly of an apparent heart attack during the showcase at Cadillac Ranch. Jacob, 20, was born in California and moved to Nashville with her family when she was 14. She toured as Jason Aldean's opening act after her debut album, Breaking All the Rules, was released in 2008. She released Strong Like Me, an EP for the Nashville to You label, last year.