Neil Patrick Harris is remembering his on-screen dad James Barrie Sikking after he lost his battle with dementia at the age of 90.

After the veteran actor’s death was confirmed on Sunday, July 14, Harris, 51, took to his Instagram to pay his respect to Sikking, who played Harris’s father on the ‘80s sitcom Doogie Howser, M.D from 1989 to 1993.

“Jim Sikking played my dad in Doogie Howser, MD, and was one of the kindest, wisest, funniest, and most generous people I’ve ever known,” Harris began his tribute, which was accompanied by a picture of the late actor.

The How I Met Your Mother alum emphasised that Sikking was “a true professional,” but beyond that, “He treated everyone with respect, taught me countless lessons, yet always had a spark of mischief in his eyes.”

‘It was an absolute honor to be his son. My condolences to his actual family for their loss,” Harris concluded.

People Magazine confirmed the sad news over the weekend, reporting that the Hill Street Blues star died “peacefully at his Los Angeles home surrounded by family.”