William P. Kelley passed away peacefully, at home, following a lengthy illness, in the early hours of April 6, 2017. Bill was born on April 7, 1962 to Thomas and Margaret Kelley of Mattapan. He was the fourth of their seven children. Bill was preceded in death by his beloved mother, Margaret. Bill graduated from BC High in 1981 and from MIT in 1985 with a degree in Electrical Engineering. At MIT, Bill became the first Catholic President of Zeta Beta Tau Fraternity, a traditionally Jewish Fraternity. He went on to work for Adams-Russell, GTE, and then for General Dynamics. Professionally, Bill developed groundbreaking communication equipment and satellite prototypes; one of his contributions can be seen in the National Air and Space Museum in Washington D.C. Bill was the recipient of many professional awards and was held in high esteem by his colleagues whom he, in turn, held in the highest regard. Bill was also an amateur magician, which led him to volunteer at church, Sacred Heart School, and community functions bringing joy and entertainment to all who saw him. He always had his pockets filled with tricks and would be surrounded by his nieces, nephews, and their children wherever he went. Bill loved to spend hours playing Whist and Cribbage with his parents, wife and siblings. As accomplished as Bill was professionally, it was his family who gave him the most joy. He is survived by his devoted wife Lauren (Barnes) Kelley and his two dear children, William, Jr. and Mary Louise all of Plymouth. William is also survived by his beloved father, Thomas J. Kelley, of Weymouth, his two sisters Margaret (and Martin) Joyce and Mary (and Patrick) Hurley of Braintree. He is survived by his four brothers Bernard (and Kathryn) Kelley of Brockton, Thomas (and Deborah) of Bridgewater, Arthur (and Paula), and Michael (and Anne) of Braintree. Bill dearly loved his brothers and sisters and their families. He is survived by twenty-two nieces and nephews as well as eight great nieces and nephews. Bill was predeceased by his mother Margaret and his great niece Penelope Joy Stellman. The funeral will take place on Monday from the Cartmell Funeral Home, 150 Court Street, Plymouth at 9:15 Monday, followed by a funeral Mass at 10 a.m. in St. Kateri Tekakwitha Parish, 126 South Meadow Road, Plymouth. Relatives and friends are respectfully invited to attend visiting hours Sunday 4-7. Burial will be in St. Joseph Cemetery, West Roxbury. In lieu of flowers, donations in memory of William Kelley may be made to St. Kateri Tekakwitha Parish, 126 South Meadow Road, Plymouth, MA 02360 or Sacred Heart School, 399 Bishops Highway, Kingston, MA 02364.