(CNN/AP) — Elvis Presley’s grandson Benjamin Keough has died, a representative for his mother, Lisa Marie Presley, said. He was 27.

Keough died in Calabasas, California, Roger Widynowski told CNN Sunday.

TMZ reports that Keough died from a self-inflicted gunshot wound Sunday in Calabasas, California.

“She is completely heartbroken, inconsolable and beyond devastated but trying to stay strong for her 11-year-old twins and her oldest daughter Riley,” Widynowski said in the statement. “She adored that boy. He was the love of her life.”

Presley had Keough and actress Riley Keough, 31, with her former husband Danny Keough. She also had twins from another marriage.

Nancy Sinatra tweeted her condolences to Presley, writing, “I have known you since before your mama gave birth to you, never dreaming you would have pain like this in your life. I’m so very sorry.”

Keough had a striking resemblance to his actor/singer grandfather. Priscilla Presley was his maternal grandmother.

The Associated Press contributed to this report.