Earlier this year, in an interview with Anderson Cooper, Joaquin Phoenix and his family opened up about the death of River Phoenix, in the early morning of Halloween, 1993.

Seven years after his iconic role as Chris Chambers in Stand By Me, River was making a name for himself as more than just a talented child actor—starring in a slate of movies in the early ’90s, including My Own Private Idaho alongside Keanu Reaves. But just as America was getting to know him, he was apparently getting to know the dark depths of Hollywood in his private life.

19-year-old Joaquin and his older sister, Rain—along with Johnny Depp, John Frusciante, and a host of other young celebrities—were there at the infamous Viper Room nightclub when River overdosed at the age of 23. Joaquin was the one who called 911 while his older brother was seizing on the sidewalk outside. Rain sat on River’s chest to contain his convulsions.

It was a huge national story at the time. Joaquin Phoenix’s frantic voice, pleading with a 911 operator to send help, was played repeatedly on TV news. Today, when he recalls helicopters hovering overhead and paparazzi trying to sneak onto their property in the aftermath, it’s hard to imagine his claim that “it impeded on the mourning process” is anything but a vast understatement.

River’s rising star in his final years far outshone the rest of his siblings’ careers at the time. 19-year-old Joaquin was not nearly as well-known—having had some minor roles in TV shows and some smaller films—but River had taken him under his wing and begun mentoring him.

He introduced Joaquin to Robert De Niro’s performance as Jake LaMotta in Raging Bull and encouraged him to emulate the way subtle details can bring characters to life. According to Anderson Cooper’s summary of their conversation, River saw Joaquin’s talent before the world did, and he told him, “You’re going to be a more successful actor than I am.”

With the accolades that Joaquin has accumulated since, including the Golden Globe he won for Joker last week, and the announcement of his fourth Oscar nomination Monday morning, River’s prediction could hardly have proven more correct. Yet with all the stories he’s helped tell, there may be none as strange and fascinating as the real-life details of his family history.

The drama of River’s death is the saddest and most familiar piece of the narrative, but the story really begins in 1968, when his mother, Arlyn Dunetz—who also goes by Heart—left New York for California. Like so many young people of that time, Arlyn was drawn to the counter-culture movement that had found its footing in San Francisco and spread out from there.

It was there that she met her future husband, John Lee Bottom, and the two began traveling the coast together, picking fruit and vegetables for a living. River Bottom was born in 1970, and Rain in 1972. Much about this early era sounds idyllic, but it was around this time that the family joined a Christian sex cult.

The Children of God (currently known as the Family International) was founded by David Berg in 1968, and it was already a thriving international movement by 1972. Its foundations were in Christian apocalypticism, but Berg billed himself as the “last end-times prophet” and added more than a few of his own ideas to the belief system.

The least upsetting aspect of his additions was the idea that sex is a beautiful and holy act. With that foundation to build on—the blend of Christianity with the free-love movement—Berg, unfortunately, abused his position to twist the role of sex within the community into something that served his perverse desires.

Perhaps the most famous of the Children of God’s sexual practices was the use of “Flirty Fishing,” wherein young female members would use sex to draw in new converts. Beyond that, Berg’s edicts, distributed in so-called “Mo Letters,” declared that incest is okay, that it is a woman’s duty to participate in sex whenever a man wants it, and that children should learn about sex from a young age—both through demonstration and participation.

It was in 1974, while they traveled as missionaries for the cult—moving around South America and the Caribbean—that John and Arlyn had their third child, Joaquin Rafael Phoenix. They were living in Puerto Rico at the time, but they never stayed in one place for long. In 1977 the family left the Children of God, citing a disillusionment with many of these sexual practices, and with Berg’s greed. They chose a new name for themselves—Phoenix—to mark this new beginning.

Sadly, their escape from the Children of God was too late to save their oldest child from trauma. According to an interview with River before his death, he said that he had “made love” at the age of four. He talks about blocking out a lot of experiences from that time, but when he became interested in sex again at the age of 14, his parents provided a tent where he and his girlfriend could have privacy.

There’s no way of knowing how things might have turned out differently for River if his early years had provided more stability and less exposure to the world’s darkness. He may have avoided addiction and death, but it’s also likely that the world would never have heard of him or any of his siblings. It was while his parents were traveling missionaries, living in a rat-infested shack in Caracas, that he and his siblings learned to perform on the streets, passing out Children of God leaflets and collecting change.

Time is the Killer ft. Michael Stipe (piano version) (Rain Phoenix) [OFFICIAL MUSIC VIDEO]www.youtube.com

With very little provided by Berg’s “church,” the children fed themselves from what they could earn through busking. When the family eventually landed in Los Angeles and Arlyn got a job working for a casting director, the children’s experience performing was directed toward careers in acting and music.

Whatever judgments we might make about the family’s history—whatever blame we might want to lay on the parents—the surviving members of the family remain close. They appeared together in the 60 Minutes interview, discussing River’s memory.

In 2012, Arlyn Phoenix co-founded the River Phoenix Center for Peacebuilding to promote peace and sustainability around the world. It was the same year that Joaquin starred as Freddie Quell in The Master—an exploration of cults and addiction, and a thinly veiled critique of Scientology. Last month, Rain Phoenix released an album called River, inspired by the memory of her brother.