The couple will exchange wedding vows in a 6:30 p.m. ceremony June 10 at Hilton Hotel in Idaho Falls.
Miss Milligan is the granddaughter of Loyal Cornelius of Spring City. She is the sister of Tara Sprengel, Melonie Murphy, BreeAnn Duell and Courtney Milligan.
She is a member of Christ Community Church.
Mr. Brown is the grandson of Jerry and Shirley Freeman of Georgetown, Shirley Pruiett of Cleveland and the late Marvin Brown.
He attended Walker Valley High School and is a member of Calhoun First Baptist Church.