Kelly Clarkson said it herself: when Dolly Parton asks you to sing something, you just shut your mouth and do it. Clarkson has begun her "Studio Sessions" residency in Las Vegas, and, as she explained from the stage, she was taking requests. Some requests. She posted a pic of the marquee at Caeser's Palace that advertised both her and Dolly Parton's shows. "think this is a sign I should cover a Dolly song at one of my shows…. but which song?" she wrote alongside the pic. At that point Dolly herself entered the chat. "Hey Kelly," she commented under the post. "I think you should sing 'I Will Always Love You' because I think you do one of the best versions of that song that I have ever heard. Whitney (Houston) and I would both be proud…." Before singing the song, Kelly explained, "Here’s the thing. This is how much I love Dolly Parton because when Dolly Parton asks you to sing something, you just shut your mouth and do it. And I love Whitney Houston as well. She’s one of my biggest influences."