Melissa Mathison, a screenwriter best known for her work with Steven Spielberg and her marriage to Harrison Ford, has died. She was 65.

Her brother, Dirk Mathison, confirmed to Variety that she died on Wednesday in Los Angeles. Dirk told The Los Angeles Times that the cause was neuroendocrine cancer.

Mathison and Spielberg reunited this year. She wrote the script for his upcoming adaptation of Roald Dahl’s The BFG, which opens in July 2016.

Her first produced screenplay was the 1979 adaptation of The Black Stallion. In 1982, she wrote the script for E.T.: The Extra Terrestrial and earned an Oscar nomination for it. The film remains one of the most beloved family movies of all time and some consider it among the best films ever made. Mathison’s understanding of children was the backbone of the film.

With E.T. on her resume, Mathison continued to write family films. Her other credits include The Escape Artist (1982), a segment in Twilight Zone: The Movie (1983), The Indian In The Cupboard (1995) and Martin Scorsese’s Kundun (1997).

“Melissa had a heart that shined with generosity and love and burned as bright as the heart she gave E.T.,” Spielberg said in a statement to the Times.

Mathison was also married to Ford for 21 years. The couple divorced in 2004 and had two children, Georgia and Malcolm.