Sister Wives' Aspyn Brown Is Engaged! Inside Their Sweet Love Story

Another Brown will soon be a bride!

Aspyn Brown, the daughter of Sister Wives‘ Kody Brown and his third wife Christine, is engaged to fiancé Mitch Thompson, the couple exclusively tells PEOPLE.

“We are both so excited to start our life together,” says Brown, 22, who met her soon-to-be husband during a family party at her parents’ house.

“We were raised in the same church group, and I had a little crush on him,” she adds. “We went different directions until a rally some of my family attended in Utah, where we both happened to be. My dad’s brother asked what ever happened between us, which was nothing, because neither of us did anything about it. So I decided to call him.”

Thompson, 25, popped the question Dec. 30, during a trip to Seattle, where they were visiting his mother.

“We got dressed up and took a walk to the waterfront before dinner, where he got down on one knee and asked me to marry him,” says Brown. ” I was so happy, I said yes immediately and pulled him up to kiss me before he could even put on the ring.”

While the pair have yet to set a date, they plan to keep their upcoming “I do’s” simple.

“The dream wedding is anytime, anyplace just as long as we are getting married to each other,” she says. “And some Scottish themes mixed in!”

Sister Wives airs Sunday at 8 p.m. ET on TLC.