OK! EXCLUSIVE: Nicole & Paris: Race to the Altar?

As rival and former The Simple Life co-star Nicole Richie shows off her engagement ring from Joel Madden, Paris Hilton can only dream of the day Doug Reinhardt will pop the question. A source tells OK! that Paris is desperate for her boyfriend to propose. And there's more than romance at stake!

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"Paris and Nicole have always had a competition going on between them," the source says.

Now Paris wants to settle down with her own Mr. Right and have kids — just like Nicole.

"Paris is happy for Nicole," says the source. "It's just that she feels it's time for her to enjoy the same kind of happiness Nicole has found."

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The source adds that Paris is devastated when she travels with Doug to somewhere romantic — say, France, or Brazil — and returns without an engagement ring.

She also did not get one on Feb. 17, her 29th birthday.

"Doug's very much in love with Paris," says the source. "The question is how long is Paris prepared to wait?"

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