Demi Lovato's Father Dies

Demi Lovato speaks during the 8th annual National Children's Mental Health Awareness Day in The Theater of Performing Arts at the University of The District of Columbia on May 7, 2013 in Washington, DC -- Getty Premium

Demi Lovato's father, Patrick Lovato, has passed away.

The "Give Your Heart A Break" singer's older sister, Dallas Lovato, announced the sad news on Twitter on Saturday, writing, "Rest in peace daddy I love you."

A rep for Demi confirmed the news to E! News.

PHOTOS: Demi Lovato

While Demi has not commented on her father's passing, her mother, Dianna De La Garza thanked well-wishers for their condolences on Twitter, writing, "Thank you for the outpouring of love and prayers. Ya'll are amazing!"

Additionally, Simon Cowell, Demi's "X Factor" boss Tweeted, "My thoughts are with you Demi. X."

PHOTOS: Stars Who Got Their Start At Disney

Further details regarding the cause of Patrick's death have yet to be released.

In 2009, while speaking with the New York Daily News, Demi said she had long been estranged from her father, who left the family when she was 2 years old.

"The last time I talked to him was two years ago," she said at the time. "You try to have faith in somebody, even when you're the last person that believes in him. But when somebody lets you down after you've been the only one there for them, and so many times, you don't know what else to do."

The singer said she was forced to sever all ties with her father in order to protect herself emotionally.

PHOTOS: 'The X Factor' Team

"I had to cut off all connection. It was hurting me too much," she told the paper.

Just last week, Demi Tweeted about her devotion to her stepfather, Eddie De La Garza (who uses Twitter handle redraider30).

"I hate calling @redraider30 my 'step dad' because he has literally been the greatest dad a girl could ever hope for," she wrote on June 16.

-- Erin O'Sullivan

Copyright 2013 by NBC Universal, Inc. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.