Miley Cyrus has a sexy new roommate – her 19-year-old boyfriend!

The 17-year-old Disney tween queen recently moved hunky Australian actor Liam Hemsworth into her family’s Toluca Lake, Calif., home – after informing her parents she’d move out if she didn’t get her way!

"In the end, Billy Ray and Miley’s mom, Tish, decided they’d rather have Miley under their roof with Liam than not knowing where she is at night," a family friend told The ENQUIRER.

But they did insist on separate bedrooms!

The Hannah Montana star began dating Liam during the summer while filming the movie The Last Song.

The relationship heated up quickly, and Miley began pressuring her parents to let her move in with Liam, the source says.

Billy Ray and Tish agreed to a compromise – they’d let Liam move into the family guest room, according to the source.

If the bizarre living arrangement sounds familiar – that’s because it is.

In early November 2008, Billy Ray allowed his then-15-year-old daughter to move Justin Gaston – her boyfriend at the time – into the family residence.

"Billy Ray believes it’s better to keep Miley on a short leash and to monitor her, rather than alienating her and risking a rebellion," the source said.

"Whatever happens in her relationship with Liam, her parents want Miley with them for as long as possible."