On Tuesday, The Lodge actress, 33, shared a photo of herself smiling next to Lisa Marie at an event held Sunday, Jan. 8, to celebrate Elvis Presley's birthday at the Formosa Café in West Hollywood.
Lisa Marie died Jan. 12 at age 54 after being rushed to a Los Angeles hospital for a possible cardiac arrest.
"I feel blessed to have a photo of the last time I saw my beautiful mama. Grateful @georgieflores georgieflores for taking this. ❤️," Keough wrote in the caption.
During a memorial service for Lisa Marie held at Graceland in Memphis, Tennessee, this past Sunday, Keough's husband Ben Smith-Petersen revealed that the pair are parents to a daughter while reading aloud a tribute on behalf of Keough, who was seated in the front row.
"I'm eternally grateful to have spent 33 years with you. I'm certain I chose the best mother for me in this world... I remember everything. I remember you giving me baths as a baby. I remember the way you would cuddle me ... and the way you smelled," read Smith-Petersen onstage.
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"I remember all the notes you'd leave in my lunchbox every day. I remember the feeling I'd get when I'd see you picking me up from school ... I remember how it felt to be loved by the most loving mother I've ever known. Thank you for showing me love is the only thing that matters in this life. I hope I can love my daughter the way you loved me, the way you loved my brother and my sisters," he continued. "Thank you for giving me strength, my heart, my empathy, my courage, my sense of humor, my manners, my temper, my wildness, my tenacity. I'm a product of your heart.
"I hope you finally know how loved you were here. Thank you for trying so hard for us," he concluded for Keough. "If I didn't tell you every day, thank you."
John Sciulli/WireImage Riley Keough and Lisa Marie Presley in 2012
Lisa Marie is survived by her mother Priscilla, 77; and three daughters, Riley and twins Finley and Harper Lockwood, 14, and her granddaughter. Lisa Marie was preceded in death by her son Benjamin Keough, who died by suicide at age 27 in 2020.
In December, Riley spoke to PEOPLE about her upcoming show Daisy Jones & The Six and said her mom reminded her of her character in the show.
"My mother is certainly an inspiration to me," said Keough, adding that Lisa Marie was "a very strong, smart woman."
She continued, "I was raised by somebody who did their own thing and didn't really care what other people thought. She was definitely inspirational to me."