Gary Coleman lived without any kidneys for nearly 25 years

If you know Gary Coleman, it's likely due to his iconic performance as the precocious orphan Arnold Jackson on Diff'rent Strokes. You may know that Coleman stayed around 4'8" his whole life due to a kidney condition. Gary, Peacock's new documentary about the troubled life of the late actor, reveals something few fans know — Coleman lived without any kidneys for nearly 25 years.

"The kidney that had been transplanted" into Coleman's body at the age of 5 and allowed him to make it to adulthood, explains lifelong friend Dion Mial in the doc, "was absorbed by the body. So from Dec. 1, 1985, until his death [in 2010], Gary lived without a single kidney in his body."

Gary traces Coleman's life from his humble origins in Zion, Ill., to superstardom on Diff'rent Strokes before he'd even reached teenagedom, to his rocky adult life, which was beset by turbulent relationships, exploitative financial entanglements, and a struggle to maintain his acting career.

Coleman's mother Sue remembers that "at about 2 years old, Gary started to run a temperature, and that's when they found out that he had this congenital kidney defect." Coleman was diagnosed with  focal segmental glomerulosclerosis, a degenerative kidney disease which causes irreversible internal scarring.

"When he was 5 1/2, we got the news that they had a kidney for him," Coleman's mother says. Coleman's body quickly took to the new kidney and he quickly recovered in kind. "Two weeks after he had his surgery he was standing on his head," she recalls. Coleman himself concurred in a segment of archival audio: "Even when I was 5, I was the do or die, never say die, 'I'll be back' kind of person. That was the kind of kid I was."

It was the medication Coleman began after his transplant which stunted his growth. Mial explains: "the immunosuppressant drugs brought about the fullness in his face. Ironically, it was his diminutive size and the fullness in his cheeks that created Gary Coleman as we know him." He recalls that "the prognosis was, if we're lucky, Gary would live to the age of 12, and at that point would require another kidney transplant."

Coleman would live well past the age of 12, but in 1985, when he was 17, he grew sick. The transplanted kidney was re-absorbed into Coleman's body, leaving him without a single kidney. Coleman had to undergo dialysis three days per week, four hours per day for the rest of his life.

While Coleman's health faltered during Diff'rent Strokes' final years, he struggled to make it through scenes, and not everyone was so understanding. Mial recalls "showing up to set one day, Gary was in the middle of a scene, completed the scene, bent over and threw up."

Diff'rent Strokes' hair stylist Joann Stafford Chaney says Coleman "spent a lot of time with me, so the producers asked me, 'What's going on? How's Gary doing?'" She told them "Gary's sick... the studio said, 'Okay let's go down for two days until Gary's better.'" But she saw Coleman's father Willie "huffin' and puffin'. He said, 'Who the hell do you think you are? Why did you have them cancel the show?"

Want more movie news? Sign up for Entertainment Weekly's free newsletter to get the latest trailers, celebrity interviews, film reviews, and more.

Coleman's costar Todd Bridges also remembers the senior Coleman's lack of sympathy for his son. "I remember the time when Gary was throwing up, I overheard Willie saying, 'You gotta get out there and you gotta work. You got people depending on you, you gotta do what you gotta do."

Diff'rent Strokes was canceled in 1986, a year after the trouble began with Coleman's last kidney. During its peak, Coleman became the highest-paid child actor of his generation, earning $100,000 per episode of the sitcom. His health would abide until 2009, when he began to suffer seizures. He died on May 28, 2010 at age 42 after a fall in his Provo, Utah, home left him with an intracranial hemorrhage.

"He had a spirit about him," Coleman's mother remembers. "'I'm going to master this, and I'm going to do what I want to do regardless.'"

Gary is currently streaming on Peacock.