Mrs. Miller succumbed to injuries suffered in a fall a few months ago in Napa, where she had a home. She was 79.

As the only surviving child of Walt and Lillian Disney, Mrs. Miller was the president of the Walt Disney Family Foundation and co-founder, with her son, Walter Elias Disney Miller, of the Walt Disney Family Museum. Last year more than 100,000 people visited the museum, which is on track to hit 150,000 in 2013.

She read her father’s original dedication fifty years later to the day at the birthday celebrations of Disneyland on July 17, 2005 and organised the development of The Walt Disney Family Museum in San Francisco. The museum opened in October, 2009.

Diane Disney Miller wrote the foreword to the book Walt Before Mickey by Timothy Susanin. The book covers the early years of Walt Disney’s career.

Animation historian Michael Barrier reports that Miller, in August 2007, sent a fax to a number of executives at the Walt Disney Company, denouncing Neal Gabler’s biography of Walt Disney published in 2006, titled Walt Disney: The Triumph of the American Imagination, as “a monstrous piece of libelous junk. My parents were not the people he creates in this book, and I cannot understand why all of you who aided and abetted Gabler in writing this book, and who praise it and promote it, can do so without suffering serious qualms.”

“She was totally devoted to the memory of her father. She obviously just worshiped him, and everything she did at the museum was to honour him, and to be sure that people knew the accurate story,” said Nancy Bechtle, who served with Mrs. Miller on the San Francisco Symphony board and recently helped her find a new director for the museum.

A resident of the Bay Area since the mid-1980s, Mrs. Miller was a benefactor to the Symphony and Napa’s “Music in the Vineyards”.

Diane Marie Disney was born Dec. 18, 1933, an event that caused the Los Angeles Times to proclaim “Mickey Mouse has a daughter.” She was educated at the University of Southern California, where she met Ron Miller, a member of the football team, on a blind date after a Cal-USC game.

She is survived by her husband; children Christopher Miller, Joanna Miller, Tamara Diane Miller, Jennifer Miller-Goff, Walter Elias Disney Miller, Ronald Miller and Patrick Miller and grandchildren.

Services will be private. A public celebration at the museum is pending. In lieu of flowers and gifts, donations may be made to the memorial fund that the Walt Disney Family Museum has created in honour of Diane Disney Miller.