The Zola actress shared a special moment on Instagram of her and Lisa Marie, who died on Jan. 12 at age 54. In the photo, the two of them are captured sitting side-by-side at a restaurant, softly smiling into the camera.
"I feel blessed to have a photo of the last time I saw my beautiful mama," Riley captioned the Jan. 24 post, adding that she's "grateful" to Dumplin' actress Georgie Flores for snapping the pic.
The snapshot appears to be taken at Elvis Presley's 88th birthday party tribute on Jan. 8, which they celebrated with Elvis director Baz Luhrmann and actor Austin Butler.
Lisa Marie—Elvis' only child—is survived by Riley, who she shared with ex Danny Keough along with late son Benjamin Keough. She was also mom to 14-year-old twins Harper Lockwood and Finley Lockwood, whose dad is her ex Michael Lockwood.
Riley—who will inherit Elvis' Graceland mansion along with Harper and Finley—first publicly spoke out about Lisa Marie's passing on Jan. 20, posting a throwback photo with a red heart emoji in the caption.
During the singer's public memorial service at Graceland Jan. 22, Riley's husband Ben Smith-Petersen read a message, titled "A Letter to My Mama," which Riley had penned for Lisa Marie.
"Thank you for being my mother in this life," he said on the actress' behalf. "I am eternally grateful to have spent 33 years with you. I'm certain I chose the best mother for me in this world and I knew that as far back as I remember you."
The letter also noted that Riley and her husband have welcomed a daughter, which a rep for the Terminal List actress confirmed to E! News.
"Thank you for showing me that love is the most important things in this life," the letter said. "I hope I can love my daughter the way you loved me, the way you loved my brother and my sisters."
Indeed, Lisa Marie stood steadfast by Riley's side, which Riley recalled in 2015 when speaking about her parents' unwavering support of her passions.
"They were very open to the idea of me doing whatever I wanted to do," she told Interview magazine. "I was one of those kids who thought I could be the president of England when I grew up if I wanted to."
But no matter the path, Lisa Marie encouraged Riley to always put in her best effort.
"I grew up with my mom saying, 'Anything you do in life, you're going to have to take it seriously, and work really hard at it, and be really good at it," Riley told InStyle in 2021. "'Don't just dip your toes into things.'"
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