Lisa Marie Presley sadly died at the age of 54 on January 12 after suffering a cardiac arrest, and she was laid to rest yesterday in an emotional memorial service. During the funeral, it was revealed that Elvis Presley’s only child had been a grandmother to a previously unknown granddaughter. The singer is survived by her twins Finley and Harper Lockwood, 14, whom she shared with ex-husband Michael Lockwood.She also shared daughter Riley Keough, 33, and son Benjamin Keough with ex-husband Danny Keough.While Riley survives the late star, Benjamin tragically died by suicide in her home in 2020.During the heartbreaking memorial service held at Graceland over the weekend, Riley's husband Ben Smith-Petersen read out a letter his wife had written to her late mother. The letter subsequently revealed that Riley had a daughter, being that Lisa Marie had been a grandmother unbeknownst to her fans. "Thank you for showing me that love is the most important things in this life," the letter stated."I hope I can love my daughter the way you loved me, the way you loved my brother and my sisters."Page Six have since reported that Riley’s representative has confirmed she and Ben have a child together, with no further information being offered. Riley met her Australian stuntman husband on the set of the movie Mad Max: Fury Road, and the pair went on to tie the knot in 2015.The grieving daughter’s tribute continued: "Thank you for being my mother in this life."I am eternally grateful to have spent 33 years with you.