Filmmaker Robert Downey Sr., father of Robert Downey Jr., dies at 85

The "Iron Man" star called his father "a true maverick filmmaker."

Robert Downey Sr., the director and actor father of Robert Downey Jr., has died at 85, the Marvel movie star announced Wednesday on Instagram.

"Last night, dad passed peacefully in his sleep after years of enduring the ravages of Parkinson's," the "Iron Man" star, 56, wrote, calling his father "a true maverick filmmaker [who] remained remarkably optimistic throughout" his health battle.

"According to my stepmom's calculations, they were happily married for just over 2,000 years," he added of Downey Sr.'s wife, Rosemary Rogers-Downey, calling her "a saint" and noting that "our thoughts and prayers are with you."

Downey Jr.'s mother, his father's first wife, Elsie Ann Downey, died in 2014.

Born in 1936, Robert Downey Sr. started his entertainment career as an actor after a stint in the Army. Throughout his career, he starred in TV shows and films, with credits including "The Twilight Zone" and "Saturday Night Live" on the small screen and "To Live and Die in L.A." and "Boogie Nights" on the big screen.

However, it was his career as a director and screenwriter decades earlier that left more of an impression, including the 1969 race-based satire "Putney Swope" and the 1970 comedy "Pound," which ranks as a 5-year-old Downey Jr.'s first acting credit.

Downey Jr. also appeared in his father's 1997 movie, "Hugo Pool."