Theatre sources confirmed her death to the New Zealand Herald this morning.
Hawthorne, the daughter of well-known acting couple Elizabeth and Raymond Hawthorne, starred in Cabaret, Closer, and The Rocky Horror Picture Show, but it was her roles in movies, When Love Comes and Savage Honeymoon, in which she played wild-child Leesa Savage, that saw her breakthrough into the big screen.
Hawthorne was twice nominated for Best Actress in a TV Drama for her role in the television show Insiders Guide to Happiness.
She also starred in the TV movie Bliss: The Beginning of Katherine Mansfield.
Her mother is currently starring in TV2's new local drama, Filthy Rich.
In a 2005 interview with the Herald, Hawthorne said she was stage-struck from an early age, and entranced by what her parents and their friends did for a living.
"I just always loved acting," she said.
However, she was described as "painfully shy" and not at all confident in "media situations", by her publicist who arranged that same interview.
And Hawthorne herself conceded she was "quite shy".
"I don't think I'm painfully shy," she said, but admitted being "quite private".
The Hawthornes - dubbed an Auckland theatre dynasty - have also worked together through the years, with all actors (mum Elizabeth, sister Emmeline, as well as Sophia) having been directed by her father a number of times, and Emmeline and Elizabeth having worked together in the past.
But Hawthorne admitted to the Herald in that 2005 interview, that it wasn't all rosy, despite being a close family.
"We definitely have arguments and we have difficult times sometimes where we don't get on and sometimes we have periods of time where we don't speak to each other, but rarely," she said at the time.
