'Sister Wives' Star Maddie Brown Is Engaged, but Not Going to Live Plural Marriage

Sister Wives star Maddie Rose Brown is ready to say, “I do!”

The daughter of Kody and Janelle Brown and Caleb Brush have announced that they are engaged.

“We are making plans for a wonderful outdoor wedding, hopefully in the country,” Maddie, 19, tells PEOPLE of her upcoming nuptials.

After first getting Kody’s approval, the 28-year-old Brush, who repairs equipment in mines, surprised Maddie with a blue diamond ring after the pair stopped at a scenic look-out point while riding his ATV.

“It was cold and we were huddled in jackets and I thought he was crazy to stop,” Maddie says. “He said to come look over here. So I walked with him to the edge. He told me he could never express how much he loved me, but he wanted to spend his life trying, and went down in one knee and pulled out a box.

“I started kissing him and saying, ‘Yes, yes!’ ”

Maddie’s parents may be famous for their polygamist lifestyle, documented on TLC’s hit reality series, but the couple isn’t planning on following in their footsteps.

Watch Epic Limbo Battle: People Now Vs. TLC’s My Giant Life Costars

“We are not living plural marriage,” Brush tells PEOPLE. “We support Maddie’s family with their choice of living plural marriage and they support us with our choice in just marrying each other.”

Sister Wives

returns Sunday at 9 p.m. ET on TLC.