Demi Lovato fangirls over Kelly Clarkson's cover of 'Cool for the Summer,' says it's the 'best bday gift ever'

It's been quite an exciting day for fans of Kelly Clarkson and Demi Lovato. As many know, the two powerhouse vocalists are super tight and supportive of each other's work. In fact, Lovato even considers Clarkson her idol ... and last night Clarkson admitted she considers Lovato, "one of her girls."

Early on last night, at the Staples Center arena in LA, 33-year-old Clarkson gushed over Lovato before performing her own rendition of "Cool for the Summer" from the fan request segment of her tour.



Clarkson also revealed that she's pregnant (!) with her second child during an emotional performance of the title track from her "Piece By Piece" album. The singer broke down and had to reassure her fans that she was simply hormonal from the pregnancy. Naturally, her fans burst into thunderous applause.

In all, the night turned out to be quite a special event, but it also happens to be Lovato's 23rd birthday today. The pop star woke up to the best birthday news ever as her biggest inspiration just covered one of her songs. Lovato took to Twitter this morning and fangirled over the news to her 30 million followers.

See her tweet below:

Watch Kelly's cover of "Cool for the Summer" below:

See Demi talk about Kelly and watch the first time they sang together:

Click through for photos of Demi Lovato through the years:

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