Niall Horan and Demi Lovato Dating? 1D Heartthrob Tweets Songstress' Sister Sweet Happy Birthday, Duo Just 'Very Close Friends'

Many fans still beg the question - are 1D heartthrob Niall Horan and popular "X-Factor" judge Demi Lovato indeed dating, or just really close friends? When One Direction performed on the season two finale of the U.S.A.'s "X-Factor" back in December, Horan and Lovato were spotted whispering backstage, prompting fresh rumors that the duo is definitely "more than friends." But such dating gossip has yet to be confirmed, and the young Hollywood stars appear nothing more than two close buddies who wish to focus more on their separate, blossoming careers rather than a serious relationship. While the young musicians may not be an exclusive couple, they still consider themselves as close as family! The 19-year-old Irish crooner recently hit up Twitter to wish Lovato's younger sister Madison De La Garza a very happy birthday. How sweet!

Lovato and Horan were spotted cozying up in L.A. on several intimate occasions over the summer... prompting rumors that they were indeed a couple. Such dating gossip died down over the fall season... until the duo was recently spotted chatting one-on-one backstage at the "X-Factor" finale:

But that doesn't necessarily mean that they're a couple. Both stars have made it blatantly clear that they're way too busy to focus on romance right now. At-the-moment, the two are just very close and loyal friends. Horan was even nice enough to send Lovato's little sis Madison an adorable birthday tweet on Dec. 28:

@NiallOfficial: "Massive happy birthday to @Maddielovesyou1 have an amazing day honey! Lots of love!"

And no matter what the nature of Lovato and Horan's relationship, most fans seem to approve. According to the gossip site ThyBlackMan.com, "The fan sites are calling Niall Horan's sweet birthday tweet to Madison 'more evidence that Niall Horan and Demi Lovato are at least super close friends and [possibly] evidence of romance. ....it's 100% evidence that Niall Horan is just...sweet.'"

So what do Mstarz readers think - will Lovato and Horan's close friendship eventually blossom into a young romance?

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