Kacy Gillis, 35, of Waltham, passed away unexpectedly on July 23, 2025 at home in Waltham.
She was born on January 25, 1990 in Mansfield to Carol and William Gillis. Kacy graduated from Mansfield High School with the Class of 2008 where she was a three season athlete. Kacy excelled at distance running and was the Varsity Captain of the Cross Country and Track and Field teams.
She received a bachelor degree in Public Health from Worcester State University, graduating in 2012, and going on to a career in pharmaceuticals working in Clinical Research Operations. Kacy also worked as a waitress where her quick wit and easy ability to make friends gained her many regulars.
Kacy loved to travel and had a deep knowledge of and passion for geography. She was able quickly to identify almost any country in the world just by its outline. She went all over including to Italy, Portugal, and Mexico to name a few. On one of her favorite adventures Kacy travelled to Peru where she hiked the Salkantay Trek to Machu Picchu. And just this year, she travelled to Ireland where she kissed the Blarney Stone.
Kacy was an animal lover, she loved all animals, but she particularly loved and spoiled her two rescue cats Greg and Piper Gillis.
She was also a gardener, a generous and thoughtful gift giver, and a fantastic and inventive cook, always trying new recipes and sharing her food with others.
Kacy was strong willed and was determined to push herself, and those around her, to try new things, go new places, and embrace life’s challenges.
Kacy is survived by her long time partner Patrick Giard of Waltham; her parents William and Carol Gillis of West Roxbury; her grandparents James and Ruth Gillis of Westwood; her brother Billy Gillis of Brighton; her sister Samantha Gillis of Watertown; her two cats Greg and Piper Gillis of Waltham; and her niece and nephew cats Gus and Suki Gillis of Watertown; her godmother Eileen Creaton of Milton; and several aunts, uncles, and cousins.
Visiting hours will be held at the George F. Doherty & Sons Funeral Home, 456 High St, Dedham on Wednesday, July 30 from 4-8pm. A Funeral Mass will be held in St. Mary’s Church, 420 High St, Dedham on Thursday July 31 at 10am. Relatives and friends kindly invited. Interment will be private.
In lieu of flowers, the family requests that donations in Kacy’s memory be made to the Merrimack River Feline Rescue Society, 63 Elm Street, Salisbury, MA 01952. Donations may also be made online at: www.mrfrs.org