Robert Carradine, star of Lizzie McGuire and Revenge of the Nerds, has died aged 71.
Mr Carradine, the youngest member of a prolific Hollywood acting dynasty, lived with bipolar disorder.
In a statement, his brother told entertainment publication Deadline that he took his own life.
"We want people to know it, and there is no shame in it," Keith Carradine said.
"It is an illness that got the best of him, and I want to celebrate him for his struggle with it, and celebrate his beautiful soul.
"He was profoundly gifted, and we will miss him every day."
Known for both his film and television work, Robert Carradine enjoyed a career spanning more than 40 years.
Born in Los Angeles, he first appeared on television in Bonanza in 1971 and made his big-screen debut in the John Wayne Western The Cowboys the following year.
Carradine's breakout role came in 1984 with the risqué comedy Revenge of the Nerds, in which he played head nerd Lewis Skolnick, remembered for his abrupt, infectious laugh.
In the late 1980s and 1990s, he pursued his passion for racing, driving professionally for Lotus, according to a family statement.
In the 2000s, he returned to television, earning recognition on the Disney Channel series Lizzie McGuire as the father of the eponymous character.
Hilary Duff, who starred as Lizzie, wrote on Instagram: "This one hurts. It's really hard to face this reality about an old friend."
"There was so much warmth in the McGuire family and I always felt so cared for by my on-screen parents. I'll be forever grateful for that," the post read.
"I'm deeply sad to learn Bobby was suffering."
Work remained consistent for the actor for a time, even if the projects diminished in prestige and quality.
Then Quentin Tarantino, ever the champion of fading character actors, cast Carradine in as one of the trackers in the 2012 film "Django Unchained", after seeing a "very furry" photograph, as Carradine told Popdose.
In 2015, Carradine was cited for a Colorado crash that injured him and his wife, Edith Mani. They later divorced, after more than 25 years of marriage.
Carradine is survived by his three children, actor Ever Carradine, Marika Reed Carradine and Ian Alexander Carradine.
Ever Carradine wrote on Instagram: "Whenever anyone asks me how I turned out so normal, I always tell them it's because of my dad. I knew my dad loved me, I knew it deep in my bones, and I always knew he had my back,"
"I think it's partly because we basically grew up together," the post read.
"Twenty years' age difference really isn't that much, and while I never ever thought of him as a sibling, I did always think of him as my partner. We were in it together."
