Dylan McDermott's Mother Murder Mystery Solved

It took decades, but the murder-mystery surrounding Dylan McDermott's mother has finally been solved.

OK! NEWS: WILLIAM BALFOUR FOUND GUILTY OF MURDER OF JENNIFER HUDSON'S FAMILY

RadarOnline indicates that 45 years after her 1967 murder, police in Waterbury, Conn., reopened the investigation at Dylan's urging and determined that she was killed by her boyfriend.

OK! NEWS: JENNIFER HUDSON TAKES STAND IN FAMILY MURDER TRIAL

Dylan Tweeted, "i'd like to thank everyone for their amazing support today. It means so much to me. It's been a long hard journey that ended in victory."

Consider this: The American Horror Story actor was only 5 years old when Diane McDermott was shot. By reopening the case last year, evidence was found that pointed to her boyfriend, reputed mobster John Sponza, as the shooter. John was shot dead in 1972, and his body was discovered in the trunk of a car.