Petrea grew up on a dairy farm in Reedsville, Wisconsin and attended Zion Lutheran Grade School in Wayside. She is thankful for her Christian education. It was there that she already desired to become a teacher. She went to Concordia University Wisconsin where she studied Elementary Education with English as a Second Language as her minor. After graduating, she served as a missionary teacher in Taiwan for four years. The following five years she taught at Christ Lutheran School in Weyauwega, Wisconsin. In 2013, she married Brendan McMahon, originally from Dearborn, Michigan. They currently reside in Farmington Hills, MI. She looks forward to sharing the love of Christ at Our Savior teaching second grade.