Sheila (Mahar) O’Donnell, 61, of the Town of Onondaga, passed away on May 18, 2025 following a brief illness. Sheila was born on September 5, 1963, to Richard and Roberta Mahar, in Syracuse, N.Y.

Sheila attended grammar school at St. Vincent De Paul, then graduated from Bishop Grimes High School in 1981. She spent her whole career in the nursing field where she began at the age of 18 and rode her bike to work as a Nurse’s Aide. She graduated from Oswego County BOCES adult education program with her LPN license. Sheila then went on to graduate with an Associate’s Degree in Applied Sciences in Nursing from SUNY Morrisville where she achieved Phi Theta Kappa and Dean’s List distinctions. Sheila earned her NYS license as a registered nurse.  She also earned a Post Graduate Certificate from the University of Southern Indiana for Anticoagulation Therapy Management. Sheila worked as an RN on the Medical/Oncology nursing teams at Crouse Hospital for 10 years, followed by another 25 years of nursing service at Crouse Medical Practice in the Cardiology Coumadin Clinic in Syracuse.  

Sheila was an avid athlete in her youth and participated in soccer, volleyball, basketball, and softball.  She also enjoyed the great outdoors, embracing every opportunity to kayak, hike, fish, camp, bike, garden, and explore nature's beauty.  She traveled with family to explore Ireland, Scotland, various National Parks in the West, the Outer Banks, Assateague Island, Niagara Falls, and Puerto Rico.  

Sheila is survived by James R. Williams; her daughter, Kelly O’Donnell Mardiney; granddaughters, Heather O’Donnell and Abilene Williams; in-laws James D. (Misty) Williams; mother, Roberta Mahar; siblings, Kevin (Mary Kay) Mahar, Reenie (Mark) Distin, Tim (Lisa) Mahar, Bobbie (Rick) Lenahan, Mike Mahar, Kelly (Greg) Firenze, Daniel (Anita) Mahar, Matt (Leanne) Mahar, and Casey Cole; as well as aunts, an uncle, cousins and numerous nieces and nephews.  She is predeceased by her father, Richard J. Mahar and her nephew, Richard (Ricky) Mahar.  

There are no calling hours, but a public Catholic Mass in Sheila’s honor will be held on Thursday, May 22, 2025 at 10:30AM at St. Vincent de Paul Church (342 Vine Street, Syracuse, NY 13203).  Burial will occur following the mass at Greensprings Natural Cemetery (293 Irish Hill Road, Newfield, NY 14867).  In lieu of flowers or plants, Sheila would welcome donations made in her memory to any of the following organizations which were her favorite charities:  St. Jude Children’s Research Hospital, The World Central Kitchen, Inc., Samaritan Center, Inc. (Syracuse, N.Y.), We Rise Above the Streets Recovery Outreach, Inc. (Syracuse, N.Y.), Helping Hounds Dog Rescue, Inc. (Syracuse, N.Y.) and The Food Bank of CNY, (Syracuse, N.Y.).