The wedding rehearsal of Chris Pratt & Katherine Schwarzenegger at Rob Lowe

EXCLUSIVE

Chris Pratt and Katherine Schwarzenegger are preparing to tie the knot, and could actually do the act anytime now – because they've held a lavish wedding rehearsal at Rob Loweis at home.

Kat and Chris received family and friends on Friday at the vast Lowe property in Montecito. Preparing for the big day, Katherine stole the show in a white dress later in the day.

Come Saturday morning, Kat was still in her pajamas and slippers as she chatted with friends. We hear that the "I'm doing" will go down on Saturday, but we have no confirmation yet. It makes sense if … the rehearsal dinner is traditionally the day or the night before.

Patrick Schwarzenegger was seen nearby, just like Bobby Shriver and Patrick & # 39; s GF, Abby Champion – so, as expected … a full family affair.

You will remember … Chris jumped to the question to Katherine in January of this year and she said yes. They acted quickly, it is the least that can be said. As they say … when you know, you know.

This will be Chris's second wedding and Katherine's first. Congratulations!!!