Mark Harmon made headlines long before his "NCIS" days over a brutal custody battle — and the court case has still left a heartbreaking rift in his relationship with his drug-crazed sister Kristin! The sordid case made embarrassing headlines for Mark just as he was trying to launch a career as a movie star, in addition to smearing the reputation of the late teen idol
Ricky Nelson. An insider has told
RadarOnline that the estranged siblings
are still struggling to reconcile, as well. “Mark and Kristin have tried to let bygones be bygones,” says a source close to the family. “But there’s just too much bad blood for either of them to completely forgive and forget.”