Mimi Had A Little Lamb: Rihanna Proves She's Still Mariah Carey's Biggest Fan At Singer's Latest Christmas Residency

Source: Denise Truscello/ Dimitrios Kambouris When it comes to Mariah Carey, Rihanna continues to prove that she's the biggest lamb in her fanbase. The Bajan billionaire kept up her annual tradition of popping up at the legendary diva's Las Vegas Christmas Residency, and she clearly had the time of her life. She was seen in the crowd singing along to Mariah's "All I Want For Christmas Is You" in full support of the elusive chanteuse. The pair were also spotted hanging out backstage, where Rihanna called coming to see Mimi "a tradition." We all remember how she got Mariah to sign . . .