Actor and filmmaker Robert Downey Sr. has died at the age of 85, according to his son, Robert Downey Jr.

The “Iron Man” star announced on social media Wednesday that his father passed away peacefully in his sleep overnight after a years-long battle with Parkinson’s disease.

Downey Jr. called his dad a “true maverick filmmaker” and said he remained “remarkably optimistic” throughout his Parkinson’s battle.

Downey Sr. is survived by his two children and wife, Rosemary Rogers. Downey Jr. joked in his post that Rosemary estimated she and her husband were happily married for 2,000 years.

“Rosemary Rogers-Downey, you are a saint, and our thoughts and prayers are with you,” wrote Downey Jr.

Along with being an actor, Downey Sr. is known for writing and directing throughout his career. He made films like “Putney Swope,” “No More Excuses,” “Rented Lips,” and “Hugo Pool.”

The Hollywood Reporter reports that Downey Sr. was known for his low-budget underground projects.