His eldest son, Barton, was a director of pediatric hematology/oncology at the Cancer Institute of New Jersey, a professor of pediatrics and pharmacology at UMDNJ-Robert Wood Johnson Medical School, and the chief medical officer of the Leukemia & Lymphoma Society. Bart died on September 27, 2012. Bart's daughter Libby is Jack and Evelyn's only grandchild. She is a graduate of Dean's FIRST Robotics program and has her bachelor's degree in communications and digital media from Clarkson University. She earned her master's degree at Worcester Polytechnic Institute in 2016 and is now a Twitch streamer, Manager of Team Kitty, FIRST Robotics mentor, Chief Media Officer of Radiance Media, and Community Manager with Kongregate.