Sept. 19, 2007

They play niece and uncle on "Heroes," but are Hayden Panettiere and Milo Ventimiglia acting more like kissing cousins? The rumor mill has been churning in recent days with chatter that the age-mismatched but chemistry-laden co-stars may be getting cozy.

But in what's sure to be a crushing blow to many a fanfic forum, the easy-on-the-eyes pair adamantly deny there's anything untoward going on.

As expected, rumblings of an offscreen romance began shortly after the apple-cheeked starlet confirmed her recent bust-up with reality D-lister Stephen Colletti, whom she dated for about a year.

The talk grew louder on Emmy night, when Hayden, 18, and Milo, 30, appeared joined at the hip (or at least as close as their hips could get, given her gargantuan gown).

Not only were they seated side-by-side during the snoozer of a ceremony, but they also posed together at the Governor's Ball afterparty, where the lately ab-tastic actor put his muscles to good use by -- infantilization alert -- cutting Panettiere's meat, according to the New York Daily News.

They also enjoyed a dance interlude at the Ball, where video (via Hollywood.TV) shows the two getting touchy-feely to the oh-so-appropriate strains of "Girls on Film." Eyebrow-raising moments include some ear-whispering and a booty-shaking Hayden reaching back to graze Milo's face with her hand.

Later, TMZ.com spotted them strolling "arm-in-arm" outside another post-awards bash and boldly asked the burning hookup question, prompting Panettiere to shoot back, "I'm holding onto him because I'm about to fall over in these heels!"

But even though there are already cutesy nickname suggestions being bandied about (best so far: Halo), their reps insist whispers of a love connection are so much hooey.

"Hayden and Milo are cast mates and good friends," Panettiere's spokeswoman pooh-poohs to MSN Entertainment. "There is nothing further to their relationship and all reports to the contrary are false."

A mouthpiece for Ventimiglia, who was briefly linked to Emmy Rossum after calling it quits with onetime "Gilmore Girls" amour Alexis Bledel, is also quick to downplay the dating reports, telling us they're just "not true."

Back in December, Hayden told USA Today that Milo was "like the big brother" on the set, explaining, "He'll always raise an eye when he passes to let me know he's watching, and that makes me laugh."

As for Ventimiglia, when the paper asked what he found "attractive" about the actress, he quipped, "Ask me Aug. 21 [Panettiere's 18th birthday], and I'll tell you a zillion things."

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