【My Sister in law Reluctantly Climbed on Top】

All you really need for a Sia Halloween costume is My Sister in law Reluctantly Climbed on Topthe wig, but extra credit if you have pipes like Kelly Clarkson.

The singer donned the infamous hair piece for a low-key a cappella rendition of "Chandelier" on Facebook Live on Oct. 28. "She's one of my favorites, so I thought I'd wear a wig and be Sia," said Clarkson.

Clarkson, who has a habit of testing out soulful covers of the hottest pop songs on the road, sees the pros and cons of having a shield of bangs on stage.

"I don't know how she does this because, you know, she can't see," pondered Clarkson. "But it's also kind of awesome because you're in your own little world when you're performing."

The two pop superstars have collaborated before -- Clarkson's "Invincible" and "Let Your Tears Fall" were penned by Sia.

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