"You can look at 100 different dresses, but when you find the one, you just know," Tori says in an exclusive sneak peek at Tuesday's episode of Little People, Big World.
But before the 24-year-old said yes to the dress, she tried on plenty of frocks that just weren't quite right.
"Zach wanted something formfitting, but that dress was a little scandalous," she says after putting on one possible option. "I don't know that I could walk down the aisle in that. It doesn't leave room for anything. No eating. I couldn't have my grilled cheese sandwich."
Eventually, the future Mrs. Roloff finds the perfect one: "It's so you," mother-in-law Amy Roloff tells Tori after she emerges from the dressing room.
"We all kind of knew," Amy adds in an interview. "It complemented her very well. She looked beautiful."
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Little People, Big World airs Tuesdays (9 p.m. ET) on TLC.