On-and-off couple Prince Harry and Chelsy Davy have split yet again –and Harry’s new gorgeous sister-in-law, Pippa Middleton may be to blame!

“[Chelsy] saw the way that he was flirting with Pippa Middleton at the wedding, and it’s only natural that she felt pangs of jealousy,” a source tells In Touch, adding that the siblings-in-law have been talking on the phone since the wedding, adding insult to injury.

Aside from Harry’s budding relationship with Pippa, Chelsy wasn’t too happy with ongoing rumors that perennial partier Harry had a wandering eye and cheated on her — which she heard throughout the course of their tumultuous seven-year relationship. “Harry will never be the faithful type,” the source tells In Touch.

But even if Harry did want to take a cue from his brother and make an honest woman out of Chelsy — who’s often photographed falling out of London nightclubs after nights of partying — she wouldn’t be interested, claims In Touch’s source.

“Chelsy doesn’t want to live her life in a fishbowl,” says the source. “Even if Harry were to propose she’d say no. She doesn’t want to be a princess … [Kate Middleton] knows how to play the game, and she says all the right things. Chelsy is more of a free spirit.”

Meanwhile, naughty-by-nature Harry isn’t particularly upset about the split. “Harry knows that with his looks, charm and title, he can have practically any woman he wants, so he figures, why not play the field?”

In fact, Harry’s particularly interested in snagging an American girl next! “He wants to go to L.A. with Wills and Kate in July…He wants to conquer all of the leading ladies in Hollywood.

I say, forget Hollywood…take a pit-stop in Indiananapolis Harry!

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