ROB KARDASHIAN: Takes Out Rihanna

Kim isn't the only Kardashian dating a music superstar.

Little brother Rob was spotted on a go-karting date in Burbank, California with Rihanna Saturday night. The U.K.'s Daily Mail says after the singer beat the reality star on the race track, Rob took his date to a Hollywood nightclub.

Rob was last linked to R&B singer Rita Ora. Us Weekly says the two went on a double date with Kim and Kanye West in May.