John “Jack” P. Leonard, long time resident of South Hadley MA, passed away peacefully on March 19th 2026 at Holyoke Medical Center surrounded by his loving family.

Jack was born in Pittsfield, MA on December 6th, 1939 to Therese and Francis Leonard. He grew up in the flats of Holyoke with his siblings Donald, Joan, and Charlene alongside many close, lifetime friends. Jack is predeceased by his mother, father, and brother Donald. He attended Holyoke Catholic schools before enlisting into the United States Navy in 1957. As a Logistics Specialist, Jack was stationed in New London, Connecticut and spent time deployed to the Mediterranean during the Beirut crisis. Jack speaks fondly of his time in the military and was always proud of his service. Upon completion of his enlistment with the Navy, Jack went on to begin his career back home as a mechanical engineer and met the love of his life, Joy Bernier. The couple married and went on to have six children: Kim, Timothy, Wendy, Thomas, Kathleen, and John II. Jack is predeceased by his wife, Joy and two of his sons, Timothy and John II.

Jack emphasized an importance on family and connection. He enjoyed fishing, hunting, golfing, playing cards, and spending time with his family, friends, and pets. One of his greatest joys was cheering on his children, grandchildren, and great grandchildren in their sports and activities. A man of many talents, Jack was an incredible writer and storyteller. He was often recognized and published, winning many awards. He had a great love for cooking and has shared and passed down many cherished recipes. Jack had a great love of community. He was very involved with St. Patricks' Social Center for many years. He also enjoyed spending time with family and friends at both South Hadley and Holyoke Senior Centers.

He is survived by his sister Joan of South Hadley, sister Charlene of Virginia Beach, Virginia, children Kim (Marc) of Granby, Wendy of South Hadley, Thomas (Carly) of Chicopee, Kathleen (Lorenzo) of Madison, CT as well as grandchildren Kelly, Jennifer, Jon, Francis, Haylee, Mark, Madelynne, Shawn, Jonathan, Jordan, Madison, Robert, and Casey as well as eleven great-grandchildren, two great-great grandchildren, and numerous nieces and nephews.

He will be greatly missed by his family and friends who will cherish all the wonderful memories with gratitude as he reunites with his beloved wife Joy and their two sons.

Calling hours will be held Thursday, March 26, from 4 p.m. to 7 p.m. at O'Brien Family Funeral Home in South Hadley. A Funeral Mass will be held at St. Patrick's Church in South Hadley on Friday, March 27th, 2026 at 11a.m. Burial and Military Funeral Honors will take place at a later date. In lieu of flowers, memorial donations can be made to the The Parkinson's Foundation at parkinsons.org/donate.