Robert Downey Jr. Mourns Death of His Dad, Robert Downey Sr., at 85: 'He Was a True Maverick'

Astrid Stawiarz/Getty Robert Downey, Sr.

Robert Downey Sr., Hollywood figure and father to Robert Downey Jr., has died. He was 85.

Downey Sr. died Tuesday night in his sleep at his New York City home, Downey Jr. confirmed in an Instagram tribute on Wednesday.

The actor and filmmaker turned 85 on June 24 and was battling Parkinson's disease.

"RIP Bob D. Sr. 1936-2021…Last night, dad passed peacefully in his sleep after years of enduring the ravages of Parkinson's," Downey Jr. wrote in the caption. "He was a true maverick filmmaker, and remained remarkably optimistic throughout."

"According to my stepmoms calculations, they were happily married for just over 2000 years," he lightly joked. "Rosemary Rogers-Downey, you are a saint, and our thoughts and prayers are with you."

Downey Sr. was a native New Yorker, born in Manhattan in 1936 as Robert Elias Jr. He changed his last name for his stepfather, James Downey, when he wanted to enlist in the U.S. Army but was underage.

The actor was best known for his breakthrough anti-establishment films such as Putney Swope and Greaser's Place. He also appeared in movies such as Boogie Nights, Magnolia and To Live and Die in L.A.

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Dave Allocca/Starpix/Shutterstock Robert Downey Sr. and Robert Downey Jr.

In 1961, Downey Sr. began writing and directing low-budget 16mm films that earned an underground following. His first was Ball's Bluff (1961), about a Civil War soldier who wakes up in Central Park in the 1960s.

Downey Sr. often included his family members in his films. He included his first wife, Elsie, in four of his movies: Chafed Elbows, Pound, Greaser's Place and Moment to Moment. The two divorced in 1975.

He had two children with Elsie: daughter Allyson and son Robert Jr., who each made their film debuts in his 1970 film Pound when they were 7 and 5, respectively.

Allyson went on to star in another one of her father's film, Up the Academy, while Downey Jr.'s extensive credits include eight of his father's film from Up the Academy to Rented Lips and Too Much Sun.

In a 2016 interview on The Off Camera Show, Downey Jr. said he remembered his father being treated with "reverence."

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Cinetel/courtesy Everett Collection From left: Robert Downey Sr. and Robert Downey Jr. on set of the film Too Much Sun

Bob Peterson/Getty Robert Downey Sr.

"Particularly around the time Putney Swope came out, it really was kind of a mind-blowing satire of advertising, power, corruption," he recalled. "That's what I heard a lot, that my dad was brilliant."

"I remember an incredibly kind of thoughtful, considerate, affectionate and attentive dad," Downey Jr. said. "I choose to remember that because unconsciously there's these long swaths of time where you have a dad that's in the military or a dad that goes on business trips. My dad was almost always home or if he was on the set I was probably heading there if I wasn't there already."

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It was also his parents who introduced him to making movies, saying on the show that due to his artistic upbringing, "It never occurred to me to do anything else. Life happens."

"The way I grew up, my mom and dad were actually squares who found themselves really entrenched in this counterculture, underground filmmaking world," Downey Jr. said. "To me, it was really natural. Whether it was after hours and my dad was playing a poker name with someone who was in that world in the late 60s to him and my mom trying to beat each other for a funny one-liner for a transition scene in a movie."

Downey Sr.'s last film as a director was his 2005 documentary Rittenhouse Square. He last appeared onscreen in 2011's Tower Heist as Judge Ramos.