Lizzie McGuire star Robert Carradine has died aged 71

Robert's family said in a statement to Deadline: "It is with profound sadness that we must share that our beloved father, grandfather, uncle, and brother Robert Carradine has passed away.

"In a world that can feel so dark, Bobby was always a beacon on light to everyone around him.

"We are bereft at the loss of this beautiful soul and want to acknowledge Bobby's valiant struggle against his nearly two-decade battle with Bipolar Disorder.

"We hope his journey can shine a light and encourage addressing the stigma that attaches to mental illness.

"At this time we ask for the privacy to grieve this unfathomable loss.

"With gratitude for your understanding and compassion."

Keith admitted Robert's bipolar "got the best of him", but insisted there is "no shame" in mental illness.

He added: "We want people to know it, and there is no shame in it.

"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.

"We will take solace in how funny he could be, how wise and utterly accepting and tolerant he was. That's who my baby brother was."

Robert made his movie debut in 1972 film The Cowboys, opposite John Wayne, and he went on to appear alongside Jane Fonda and Jon Voight in Oscar-winning motion picture Coming Home.

As well as starring in Martin Scorsese's Mean Streets in 1973, he appeared opposite his brothers, David and Keith, in Walter Hill's The Long Riders.

Robert found further fame in 1984 film Revenge of the Nerds, and he played dad Sam McGuire in the 2000s TV series, and 2003's The Lizzie McGuire Movie.

Robert's half-brother brother, Kill Bill actor David Carradine, died in 2009 aged 72.