20 Things You Somehow Missed In Once Upon A Time In Hollywood
7. A Real Manson Song Was Sung

As already noted during this very list, Tarantino's use of music and the various things heard on the radio (we'll get there) during Once Upon a Time in Hollywood is quite fascinating. But it's also unexpectedly chilling on occasion, too.
You know that song we hear the various young girl members of the infamous Manson Family singing when we're first introduced to them in the movie? Well, though you no doubt didn't miss how creepy it was, you probably didn't know that this is actually an à capella version of a song written by the real-life cult leader himself, Charles Manson.
That song is called "I'll Never Say Never To Always" and could be found on the singer-songwriter's 1970 album - Lie: The Love And Terror Cult.
Thankfully, though, as confirmed by the movie's music supervisor Mary Ramos to Variety, they were informed after choosing to spend money to use the song in their feature that "no one even associated with the Mansons and the Manson family makes money off of that song." Instead, a trust was set up for the victims.