Paul Reubens, the actor best known for portraying Pee-wee Herman, died on Sunday at the age of 70 after a private, yearslong battle with cancer.

"Please accept my apology for not going public with what I've been facing the last six years," Reubens shared in a posthumous Instagram post on Monday. "I have always felt a huge amount of love and respect from my friends, fans and supporters. I have loved you all so much and enjoyed making art for you."

Reubens additionally "asked that any expressions of sympathy be made in honor of his late parents, Judy and Milton Rubenfeld, to Stand Up to Cancer or organizations involved in dementia and Alzheimer's care, support and research."

In the caption for the post, Reubens' estate added, "Last night we said farewell to Paul Reubens, an iconic American actor, comedian, writer and producer whose beloved character Pee-wee Herman delighted generations of children and adults with his positivity, whimsy and belief in the importance of kindness. Paul bravely and privately fought cancer for years with his trademark tenacity and wit. A gifted and prolific talent, he will forever live in the comedy pantheon and in our hearts as a treasured friend and man of remarkable character and generosity of spirit."

Born on Aug. 27, 1952, Reubens joined the Los Angeles-based improvisational and sketch comedy troupe the Groundlings in the '70s. It was there that he developed his Pee-wee Herman character. The character made his stage debut in 1980's The Pee-wee Herman Show, which enjoyed a five-month sold-out run and spawned an HBO special. The Tim Burton-directed Pee-wee's Big Adventure followed in 1985 and transformed Reubens' character into a household name. A sequel, Big Top Pee-wee, arrived in 1988, and the CBS children's show Pee-wee's Playhouse aired from 1986-90.

Reubens' career and public reputation took a tumble in July 1991 when he was arrested in Sarasota, Florida, for masturbating while watching a pornographic film at an adult movie theater. Several celebrities came to his defense, even as retailers like Toys-R-Us removed Pee-wee Herman toys from their shelves. Reubens retreated from the public eye for much of the decade, although he did receive an Emmy nomination for his recurring role in Murphy Brown from 1995-97.

The actor began taking on larger roles again in the late '90s and early '00s, appearing in the 1999 superhero comedy Mystery Men and the 2001 crime drama Blow, which starred Johnny Depp and Penelope Cruz. He appeared in various other projects throughout the next two decades, including Reno 911!30 RockBatman: The Brave and the Bold, Tron: Uprising, Mosaic and Legends of Tomorrow.

Reubens revived the Pee-wee Herman stage show in 2010, with the production opening on Broadway that November. Another TV movie, The Pee-wee Herman Show on Broadway, came out the following year and earned an Emmy nomination for Outstanding Variety, Music, or Comedy Special. In 2016, Netflix released Pee-wee's Big Holiday, a standalone sequel to Big Top Pee-wee and the last film to star Reubens as his most famous character, to largely positive reviews.

Through it all, Reubens sought to spread joy and positivity with his charmingly off-kilter character. "Part of me thinks, 'Wow, it'd be fun to make something super edgy.'" he told Bust in 2016. "But that's not me. Left to my own devices, I turn out stuff that's positive, uplifting and a little corny. I mean, I'm a comedian — I'm trying to make everybody happy. So at the end of the day, if you don't like corny, then I'm not your guy."

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