Speaking to Revolver, the Pretty Reckless singer revealed that she was surprised that the Hills star decided to record her track 'Blackout'.
"I wrote a pop song [called ‘Blackout’ when I was 8] and recorded it with a producer as a demo," she said. "Heidi Montag from The Hills just recently sang it and put it out as her single."
She continued: "I'm like, okay, dude, you're singing an 8-year-old's words, but that's cool. It's so funny because I didn't shop it or anything and I get this call going, 'Did you write a song for Heidi Montag'? And I'm like 'What?'"
Momsen previously commented that she occasionally enjoys watching pornography.