Usmagazine.com has confirmed that the two will tie the knot in a sunset ceremony Saturday at the Westminster Presbyterian Church in Pasadena, Calif.
Pratt said it was "totally spur of the moment" when he and Montag flew down to Cabo San Lucas, Mexico, last November and exchanged vows with $8 rings they picked up there.
Still, Montag told Us, "The minute we said our vows, I couldn't stop crying."
Outraged that they secretly eloped, Montag's mother told Us Weekly at the time that she gave their marriage "six months."
Montag and Pratt planned to make the Mexican wedding official with a trip to the Beverly Hills courthouse, but Pratt had a change of heart at the last minute. Montag, he said, always wanted a traditional wedding with family and friends and a simple, courthouse ceremony didn't feel right.
"I just want to give you the wedding of your dreams that you have been talking about for three years," he said on "The Hills" Season 4 finale last December. "I'll deal with it. It's worth it to be with you the rest of my life. We'll do it the way you want, I'm sorry, I love you so much."
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