Nicholas Brendon, Xander Harris in Buffy, dies aged 54

Nicholas Brendon was best known for his role in all seven seasons of Buffy the Vampire Slayer. (Supplied: 20th Century Fox)

Nicholas Brendon, best known for his role as Xander Harris in all seven seasons of Buffy the Vampire Slayer, has died aged 54.

In a post to his Instagram page, his family posted in a slide post saying: "We are heartbroken to share the passing of our brother and son, Nicholas Brendon."

It said he died in his sleep of "natural causes".

A family post said Nicholas Brendon died in his sleep of "natural causes". (Supplied: Instagram)

"Most people know Nicky for his work as an actor for the characters he brought to life over the years," the post read.

"In recent years, Nicky has found his passion for painting and art.

"Nicky loved to share his enthusiastic talent with his family, friends and fans.

"He was passionate, sensitive, and endlessly driven to create. Those who truly knew him understood that his art was one of the purest reflections of who he was."

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