Sarah Ferguson has penned an emotional tribute following the death of her dear friend, Lisa Marie Presley, whom she affectionately calls "my sissy".
Taking to Instagram on Friday, the 63-year-old uploaded a sweet throwback photo of the pair as expressed her deep sadness over the sudden loss.
WATCH: The life of Lisa Marie Presley
"I say hello to you every day and I love you my sissy and I will continue to say hello to you every day," she wrote. "You were my sissy, an amazing mother to Ben, Riley, Harper and Finley and a superbly loving daughter to Priscilla.
"You have been my devoted friend for many years and I am here for your family to support and love them. I am deeply saddened my sissy, you are in my heart."
Lisa, who was the only child of rock and roll legend Elvis Presley, suffered a cardiac arrest at her home in Calabasas, California, on Thursday morning.
Sarah shared this sweet snap of the duo
Hours later, her heartbroken mother Priscilla Presley confirmed her daughter had passed away aged 54. In a statement, she said: "It is with a heavy heart that I must share the devastating news that my beautiful daughter Lisa Marie has left us. She was the most passionate, strong and loving woman I have ever known."
MORE: Hollywood stars John Travolta and Tom Hanks pay tribute to Lisa Marie Presley
Lisa leaves behind four children. She had a daughter, Riley Keough, and a son Benjamin Keough with her first husband Danny Keough. Tragically, Benjamin died aged 27 in July 2020.
Lisa was last seen at the Golden Globes earlier this week
Riley, 33, followed in her famous family's footsteps and is set to star as Daisy Jones in an upcoming series based on the hit Taylor Jenkins-Reid novel Daisy Jones and The Six.
In 2008, Lisa gave birth to fraternal twin girls, Harper Vivienne Ann and Finley Aaron Love, whom she shares with her fourth husband, her former guitarist Michael Lockwood.
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