Priscilla Presley Says the 'Shock' of Grandson Benjamin Keough's Death Has Been 'Devastating'

Priscilla Presley has broken her silence following grandson Benjamin Keough's death.

On Wednesday, the Presley matriarch, 75, spoke out for the first time since Benjamin — the son of her and late ex-husband Elvis Presley's daughter Lisa Marie Presley — died by suicide on July 12 at the age of 27. In a Facebook post, she wrote, "These are some of the darkest days of my family's life."

"The shock of losing Ben has been devastating," she wrote. "Trying to put all the pieces together of all the possible whys has penetrated my soul. Each day I wake up I pray it will get better. Then, I think of my daughter and the pain she is going through as she was a doting mother. Ben’s father, Danny [Keough], who is completely lost, as Ben was his only son."

Jon Kopaloff/Getty; Copetti/Photofab/Shutterstock Priscilla Presley; Benjamin Keough

"Riley, so loving and so close to him; Harper and Finley, who absolutely adored Ben. Navarone, who struggles deeply with loss and death," she continued of Benjamin's sisters and his uncle Navarone Garibaldi, Priscilla's son with Marco Garibaldi. "Rest In Peace Ben, you were loved."

Nikki Boertman/Reuters/Landov Riley Keough, Priscilla Presley, Lisa Marie Presley and Benjamin Keough

Priscilla's message came days after Benjamin's girlfriend, Diana Pinto, penned a touching tribute to him on Instagram.

"To the most beautiful boy I have ever seen," Pinto wrote on Sunday. "You make everyone around you light up the second you step into the room. You touch every single soul around you. You love your Sunday morning toons and chocolate milk. I promise to always honor you on Fancy Fridays."

"Your laugh is heard all over the world now," she continued. "You made me the luckiest girl in the world, to have you, to hold you, to love you and to be loved by you are the only things that have ever mattered. You are my whole world and my whole life, you live with me now every day in my heart, in my soul and in my mind."

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Pinto went on to call Keough her "travel partner" and "best friend."

"I will cherish all the memories we've made together and keep them close to my heart," she wrote. "I feel your silliness within me still making me laugh. Every second of every day I think of you, now I know the true meaning of grief. Please give me strength to keep going because I don't know how I'm supposed to do this life without you."

"You will always be the love of my life, my everything," she concluded. "Big pies little pies, te amo mas que el sol y la luna mi amorsito [I love you more than the sun and the moon my love]."

Diana Pinto/Instagram Benjamin Keough and girlfriend Diana Pinto

On Saturday, Keough's older sister, Riley, 31, also spoke out about his death for the first time. In an Instagram post, Riley called him her "twin soul" and "best friend."

"Mornings are the hardest," she wrote. "I forget you're gone. I can't cry because of the fear that I will never stop. A pain that's new to me."

"You. There are no words for you," she continued. "Angel is the closest I could think of. Pure light. Baby brother. Best friend. Wild man. Intellectual. Witness to my life. Twin soul. Protector. Too sensitive for this harsh world. I hope you give me strength to endure the giant hole you’ve left in my heart. I hope you give me the strength to eat. I hope you're cradled in love. I hope you feel my love. I hope you feel god. You are god. I can't believe you've left me."

"Not you sweet Ben Ben," she concluded. "Anyone but you. I guess this is true heartbreak. I hope we meet again."

RELATED: Riley Keough Shares Touching Tribute to Late Brother Benjamin: 'This Is True Heartbreak'

In addition to Benjamin, Riley has 11-year-old twin sisters, Harper and Finley, whom Lisa Marie, 52, shares with ex-husband Michael Lockwood.

Following Benjamin's death, Lisa Marie's rep, Roger Widynowski, told PEOPLE that the star is "beyond devastated."

"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. "She adored that boy. He was the love of her life."

Lisa Marie Presley / Instagram https://www.instagram.com/p/BkRLh6Chpyc/?utm_source=ig_embed

Benjamin’s friend, musician Brandon Howard, recently told PEOPLE that the pressure to live up to the Presley family name "absolutely" contributed to Benjamin's struggles.

"That kind of pressure is definitely a part of what happened," he said. "It's a tough thing when you have a lot of pressure with your family and living up to a name and an image. It's a lot of pressure. It's almost like you're pressured into having to be a musician, having to be an actor. It was good for him to go around the world and discover himself and have his own friends. You never know what triggers it. You never know ... It's so random."