Donald Hilligoss

1944 - 2025

Mystic – Donald Martin Hilligoss, 81, passed away peacefully at his home surrounded by his family, on Thursday, September 25th, 2025.

He was born September 18th, 1944 in Anderson, Indiana, the son of the late Robert and Opal (Martin) Hilligoss.

Don lived a life of service and discovery, achieving professional and educational successes he never could have imagined growing up in Turlock, California. From 1962 to 1966, he proudly served his country as a Radio Intercept Analyst with the United States Air Force Security Service, stationed in Frankfurt, Germany.

Following his military service, Don pursued education and his interests, culminating in a distinguished career in pharmacy and medical research. He served as Clinical Coordinator of Pediatric Pharmacy Services at New York Hospital–Cornell Medical Center, later working as a Clinical Pharmacist in Pediatrics at UCLA. From 1980 to 1988, he was an Associate Professor of Pharmacy and Pediatrics at West Virginia University, where he also directed Pharmacokinetic Services at Charleston Area Medical Center.

In 1988, Don joined Pfizer Global Research and Development in New London, Connecticut, where he rose to Director, guiding groundbreaking research until his retirement in 2010. His work in pharmacokinetics and pediatric pharmacy left a lasting impact on patients, students and colleagues alike.

Above all, Don treasured his family-he is survived by his daughter, Elizabeth Hilligoss; his son, Ross Hilligoss, and his daughter-in-law, Margaret Manning. He also leaves his children's mother, Roberta (Swanson) Hilligoss, and his best friend Rita Sloan.

Don was an avid conversationalist who enjoyed nothing more than exchanging stories and ideas with friends, family and the occasional stranger. A lifelong learner and a champion of science, he was a steadfast critic of policies and politicians that served the privileged at the expense of the disenfranchised. Though Don was realist and something of a skeptic, the causes that were dearest to him betrayed the hope he held for people at large: he loved Bernie Sanders, saving the bees and gun control.

Don was a fixture in his son's home, where the humans could count on an amusing anecdote and the many animals could rely on him for a hearty pat. He was warm, insightful and unapologetically himself.

He will be remembered for so many things: his devotion to his loved ones, his signature gray sweats, his fondness for greenery, the adoration of his grand-pets and the kindness he showed everyone who had the good luck to know him. To honor his memory, consider a donation to the birds and bees, animal adoption, liberal politics or the scientific advancement of your choice.

One of Don's final wishes was to forgo traditional interment-instead he elected to transform his body into soil. A celebration of life will be planned for spring 2026, when that process is complete.