Benjamin Keough, son of Lisa Marie Presley and grandson of Elvis Presley, died on Sunday (July 12) in Calabasas, Calif. He was 27 years old.

Keough's official cause of death has not been released; however, TMZ reports that he died of a self-inflicted gunshot wound. He was Lisa Marie Presley's only son and his legendary grandfather's sole grandson; his father is Presley's ex-husband, Danny Keough.

Benjamin Keough's older sister is actor Riley Keough, 31, and his half-sisters are 11-year-old twins Harper and Finley, whose father is another of Presley's ex-husbands, Michael Lockwood. According to People, Presley is severely rocked by the loss.

"She is completely heartbroken, inconsolable and beyond devastated but trying to stay strong for her 11-year-old twins and her oldest daughter Riley," her representative relates. "She adored that boy. He was the love of her life."

Presley had a special bond with her son, and saw in Keough a striking resemblance to Elvis Presley, as she told CMT in 2012 when releasing a posthumous duet with her late father, “I Love You Because." A music video for the song is packed with family footage.

“Sometimes I am overwhelmed when I look at him,“ Presley said of her son at the time. Her song “Storm & Grace“ is also thought to be inspired by Benjamin, whose middle name was Storm.

Keough's grandmother is Priscilla Presley, Elvis Presley's widow. Lisa Marie Presley was married to Danny Keough from 1988 until 1994; she was married to Michael Jackson from 1994 until 1996, and then to Nicholas Cage, from 2002 until 2004.

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