Dave and Connie Vaughan, Jefferson City, announce the engagement of their daughter, Kelsey Vaughan, St. Louis, to Jon Elenkiwich, St. Louis, son of Dave and Sue Elenkiwich, Edina, Minn. A May 14 wedding is planned at Our Lady of Lourdes Parish, St. Louis. The bride-to-be is a 2008 graduate of Helias Catholic High School, Jefferson City, and a 2012 graduate of Saint Louis University with a B.A. in Communications. She is Director of Events at Contemporary Productions. The groom-to-be is a 2008 graduate of Edina High School, Edina, Minn.; a 2012 graduate of Saint Louis University with a B.S. in Biomedical Engineering and a Washington University graduate with a M.S. of Engineering. He is a R&D Engineer with BioMerieux.