Margaret J. O'Brien (Cullen), affectionately known as Margie, passed away peacefully on October 26, 2025, in Cocoa Beach, Florida, at the remarkable age of 94 years.

Margie was born in Woburn, Massachusetts, and was a beloved daughter of the late Garret and Mary Cullen. She was a proud graduate of St. Charles Catholic High School, Class of 1949, in Woburn, MA. Throughout her life, she took on many roles, including that of a bookkeeper, a housewife, and a cafeteria manager for Winchester Public Schools in Massachusetts.

Margie was married to her late husband, John William (Pat) O'Brien Jr., for 52 wonderful years. She was a loving and devoted mother, mother-in-law, grandmother, and great-grandmother. Her family includes her daughter Maureen O'Brien and her spouse Marcia Quakenbush of Santa Cruz, CA, and her five sons: John W. O'Brien III and his spouse Gayle of Groton, MA, the late James G. O'Brien, Joseph C. O'Brien of Tewksbury, MA, Francis X. O'Brien and his spouse the late Dann Rhone of San Francisco, CA, and Michael O'Brien and his spouse Christine of Lynchburg, VA. Margie was also a cherished grandmother to John, Michael, Callie, Shannon, and Kate, and a great-grandmother to Maddie and Rose.

Margie is also survived by her sister Elizabeth Cullen of Cocoa Beach, Florida. She was preceded in death by her siblings Mary Cullen, Garrett Cullen, Rose Manson, Ruthy Cullen, Audrey Muise, and Carolyn Griffin.

A funeral mass will be celebrated in her honor at the Church of Our Savior Catholic Church in Cocoa Beach, FL, on November 14, 2025, at 11:00 a.m. In lieu of flowers, the family kindly requests that donations be made to the St. Vincent DePaul Society Our Savior's Conference. Donations can be made at the following address: 130 Cleveland Ave, Unit C, Cocoa Beach, FL 32904, or through their website: https://oursavioursparish.org/svdp.

Margie will be dearly missed by all who knew her.