More Miley drama.

In a newly surfaced video (watch above), Cyrus, 17, urges her 9-year-old sister Noah to perform a dance to Akon's racy tune "Smack That..."

"Smack that, all on the floor. Smack that, give me some more. Smack that, 'til you get sore. Smack that, oh ooh," the girl sings.

Noah Cyrus raised eyebrows in October when she wore a "dominatrix" Halloween costume.

"We're forced to question [parents] Billy Ray and Tish's judgment," said an Eonline columnist.

"Obviously, these costumes are going to cause a stir, and the Cyrus family knows the Internet really can be a mean place—just look at all the scrutiny Miley deals with on an almost daily basis," read the E! blog. "So it seems odd they would willingly subject a 9-year-old to such criticism."