Ross Chestnut and Taylor Callaway Chestnut; son Andrew Trammell Chestnut, wife Heather Bee Chestnut, and daughter Christina Callaway Chestnut and son Zachary Blake Chestnut. Hal and Erma Ruth’s long marriage was a source of great strength and satisfaction to both of them. Erma Ruth earned a bachelor’s degree in mathematics from the University of Colorado and a master’s degree in guidance and a doctorate in education administration, both from the State University of New York at Albany. She accompanied Hal on many of his trips around the world, especially when he held leadership positions in IFAC and IEEE.