Catelynn Lowell and her fiancé, Tyler Baltierra, both 20, are finally saying "I do!" The Teen Mom couple will walk down the aisle at their July 13 dream wedding after facing countless challenges over the past four seasons. They've not only dealt with their wrenching decision to place their daughter, Carly, up for adoption, but with a troubled home life that included their parents’ drug addiction, neglect and verbal abuse. But they've faced each with compassion and mutual support. “We’ve been together almost eight years, and I honestly think that we’re soulmates,” Catelynn tells In Touch. The two, who began dating in seventh grade, have decided on a Renaissance-themed ceremony in their home state of Michigan, along with 220 guests and a six-tiered, multi-flavored wedding cake. And Catelynn and Tyler have their hearts set on 3-year-old Carly as flower girl. “I really want her to be there,” says Tyler, “We wouldn’t even be getting married if it wasn’t for her.” Their first dance? Jason Mraz’s very fitting, “I Won’t Give Up.” Read more about Catelynn and Tyler’s nuptials in the new issue of In Touch, on newsstands now!