River Phoenix in 1988.Photo: George Rose/Getty

Actor River Phoenix, star of “Stand By Me,” poses during a 1988 Los Angeles, California, photo portrait session. Phoenix, a rising young film star, tragically died in 1993 outside a Sunset Strip nightclub of a drug overdose.

River Phoenix’s family members are remembering him on what would’ve been his 52nd birthday.

On Tuesday, the late actor’s mother Arlyn “Heart” Phoenix shared a throwbackblack-and-white photoof herself and River alongside a heartfelt caption that began, “On August 23, 1970, at 12:03 PM in a little town called Madras in Oregon, I became a mother.”

She continued, “52 years ago I experienced a LOVE beyond all of my understanding which transformed my life and multiplied in and out of my being. During the past years since I have posted on Facebook, I have shared how deeply his life and passing affected me. He remains a guiding light on my pathway forward.”

Heart concluded, “When I am reminded of the lyrics to a song River wrote at 15, ‘RUN TO THE RESCUE WITH LOVE AND PEACE WILL FOLLOW,’ I am ever grateful for this inspiration which is foundational to the work ofThe River Phoenix Center for Peacebuilding!”

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The actor’s younger sisterRain Phoenixposted her own tribute to River,sharing a photoof the actor holding up one hand, concealing half his face.

“Happy birthday River 💙,” she wrote, going on to quote lyrics from her song “Immolate”: “I’m only as good as your friendship has made me … "

“On the death of a friend, we should consider that the fates through confidence have devolved on us the task of a double living, that we have henceforth to fulfill the promise of our friend’s life also, in our own, to the world,” added Rain, 49, attributing the latter passage toHenry David Thoreau.

Riverwas just 23 when he diedoutside the Viper Room in West Hollywood, California, due to a drug overdose on Oct. 31, 1993. He made his mark on the world after starring in the beloved filmsStand By Me(1986),Running on Empty(1988) andMy Own Private Idaho(1991). His final film,Dark Blood, was completed in 2012.

RELATED VIDEO: Joaquin Phoenix Recites Late Brother River’s Song Lyrics in Emotional Oscars Speech forJoker

“I’ve been a scoundrel all my life. I’ve been selfish. I’ve been cruel at times, hard to work with, and I’m grateful that so many of you in this room have given me a second chance,” hetold the audience. “And I think that’s when we’re at our best, when we support each other. Not when we cancel each other out for past mistakes, but when we help each other grow, when we educate each other, when we guide each other towards redemption. That is the best of humanity.”

“When he was when he was 17, my brother wrote this lyric,” Joaquin, 47, went on. “He said, ‘Run to the rescue with love and peace will follow.’ "

Later that year, Joaquinwelcomed his first childwithRooney Mara: sonRiver, named after Joaquin’s late brother.

source: people.com