The “Emily in Paris” star says the revelation came during her first Genesis concert as an adult.

It wasn’t until adulthood that Lily Collins realized Genesis was not a fever dream.

The Emily in Paris star and daughter of Genesis frontman Phil Collins recently opened up about her unusual relationship to the band’s music during a visit to Watch What Happens Live, after being asked to name her favorite tune from the Rock and Roll Hall of Famers.

“You know the funny thing is that I have these memories as a kid of songs that I don’t know if they’re actually real,” she told host Andy Cohen. “Because they were like, in my head, as I was maybe in the womb.”

Laughing, the actress explained, “But then when I went to the first Genesis concert that I actually remembered as an adult, there were songs that came on that I went, ‘That’s a real song?! I thought that was just a melody in my head.’”

Hearing her father’s music with a crowd was a real revelation for Lily, who added, “It was really weird.” That said, she had no problem naming her favorite Phil Collins song: “Probably ‘In the Air Tonight,’” she said. “There’s too many.”

Back in 2022, Lily, who is the daughter of Collins and Jill Tavelman, spoke to Glamour about beginning her career in her father’s shadow and explained that despite wanting to build a name for herself, she never considered changing her last name to distance herself from his fame.

“I’m so incredibly proud of what my surname represents, for what my dad’s done,” she told the outlet. “And I’m an incredibly proud daughter, but I am going on my own path, my own journey. I didn’t want to change my last name.”

She added that at the same time, being introduced as “Phil Collins’ daughter” was often frustrating. “I so badly wanted to always fight that, because it wasn’t the place that I was coming from. And so I am really proud of where I am today because I know how hard I work,” she said.

That same year, the Love, Rosie star attended Genesis’ final performance at London’s O2 Arena, closing out their The Last Domino tour. While Phil provided vocals for the band, health issues made him unable to do the drumming, which led to his son Nic joining the group on tour.

“Tonite [sic] marks the end of an era,” Lily wrote after the show, sharing footage from the performance and photos of herself backstage. “To have witnessed this last show was truly the memory of a lifetime and an event I shall hold in my heart forever. Endlessly grateful doesn’t begin to do it justice. So much love was left on that O2 stage and an even bigger amount shared between an audience who didn’t want it to end.”

She added, “Thank you @genesis_band for the memories, thank you dad for being such an inspiration and thank you @nic_collins for making me the proudest sister there is. 50 years of songs later and still generations more to celebrate you long after this tour has finished…”

You can hear Lily talk about her father’s music in the WWHL clip above.