Age-Inappropriate Hookup Rumor of the Day: Demi Lovato, 18, Linked to Ryan Phillippe, 36

Wonderwall, Monday, July 18, 2011, 2:05pm (PDT)

By Kat Giantis

• Last week, Demi Lovato insisted she had sworn off dating. "I'm so busy trying to figure my own self out," the 18-year-old rehab grad explained to Ryan Seacrest. "There's no crush, there's nobody. I have a pact with my friends right now, literally no boys."

  But, she added, "Whatever happens, happens."

  Now, rumors are rampant that something has happened with none other than Ryan Phillippe, who, at 36, is twice her age (or, as we like to see it, an entire college freshman older than she is).

  E! News says Demi has been "quietly dating" the romantically short-attention-spanned actor for the last couple of months.

  A source says the pair started off as casual but "quickly heated up," although things are said to have "cooled a bit" since Phillippe became a father for the third time on July 1, when ex-girlfriend Alexis Knapp gave birth to daughter Kai (he is also dad to Ava, 11, and Deacon, 7, with ex-wife Reese Witherspoon).

  "It was really hot and heavy for a while," alleges the insider, who says Demi wasn't aware of the stork delivery "until it basically happened. It kind of threw her for a loop."

  Another reason cited for the apparent cool-down: Demi, who stepped out Sunday night in a T-shirt that read, "The Only Coke I Do Is Diet," has been busy promoting her new single and video, "Skyscraper."

  "They were just hooking up," an insider poohs-poohs to Us Weekly. "It was nothing serious."

  While their respective reps remain mum, a Phillippe confidante assures Wonderwall that the hookup whispers are untrue, while another snitch tells E! that he's "totally single."

  Still, he wouldn't be the first older guy to catch her eye. Before Demi went to rehab for "emotional and physical issues," she was rumored to be dating notorious starlet defiler Wilmer Valdarrama, 31.

  They allegedly reconnected after she left treatment but recently called it quits, with a source telling the New York Post, "The age difference meant they were in completely different places in their lives."

  As for Ryan, he appears to be off again with Amanda Seyfried, whom he hooked up with last Halloween. Us adds that he's yet to take a paternity test to confirm he spawned with Knapp, although he was reportedly present for the delivery.

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