James B. Sikking, ‘Hill Street Blues’ and ‘Doogie Howser, M.D.’ Star, Dead at 90

James B. Sikking, known for his notable leading roles on Hill Street Blues and Doogie Howser, M.D., has died at the age of 90. The actor’s death was caused by complications related to dementia, according to his publicist Cynthia Snyder (via Variety). He died at home in Los Angeles on Saturday, July 13.

Sikking’s career began in the mid-1950s, when he made his acting debut as an uncredited union sergeant in the film Five Guns West. Over the next three decades, the actor would take on roles on popular series such as General Hospital, M*A*S*H, Hawaii Five-O, Little House on the Prairie, Bonanza, and more before landing the role of Lieutenant Howard Hunter on Hill Street Blues.

The primetime police drama premiered on NBC in 1981 and ran for nearly 150 episodes through 1987. The series was created by Steven Bochco, who would later work again with Sikking on the medical sitcom Doogie Howser, M.D.. The ABC series premiered in 1989 and ran for 97 episodes, concluding in 1993. Sikking starred in the role of David Howser alongside a young Neil Patrick Harris, who played his son.

“Our family first met James Sikking at an ABC meeting in 1990 while he was starring in Doogie Howser, M.D. alongside [Neil Patrick Harris],” veteran television broadcaster Ray Cole shared on social media over the weekend. “We later had the pleasure of hosting him during a visit to Iowa. A favorite of producer Steven Bochco, James was a talented actor … and lovely man.”