(CNN)Fantasy novelist Ursula K. Le Guin died Monday afternoon in her Portland, Oregon, home, her son Theo Downes-Le Guin said. She was 88.
"It was unexpected at that moment," Downes-Le Guin said. "Her health had not been great."
The acclaimed author penned everything from short stories to children's books, but was best known for her work in the science fiction and fantasy realm.
She won numerous Hugo awards, science fiction's most prestigious honor, for titles including "The Left Hand of Darkness," "The Dispossessed," and "The Word for World is Forest."
She had lived in Portland for almost 60 years and had lived in the same house for the past 36 years.
Downes-Le Guin described growing up with a mother with such a rich imagination. "She was an extraordinary conversationalist," he said. "There was never a wasted conversation."
Last year, Houghton Mifflin Harcourt published a book of her essays titled "No Time to Spare: Thinking About What Matters."
She had also written books on poetry and writing that are still unpublished, Downs-Le Guin said.
Writer Shannon Hale lamented Le Guin's death.
"She is a master storytell(er). She is fierce and frighteningly smart and does not tolerate fools. Her EARTHSEA books are a revelation," Hale tweeted.
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