Margaret (Maggie) Anne Sumner (née O’Neill) of Greenwich, CT died after a courageous battle with cancer on February 20, 2026.
She is survived by her mother, Anne O’Neill of New Rochelle, siblings Jeannie Loferski (Michael Loferski), Catherine McWilliam (James McWilliam), Sheila O’Neill (Kerry Metz), Tricia O’Neill (Nick Mulford) and Timothy O’Neill (Krystin O’Neill). Her father John T. O’Neill and nephew Henry “Hank” McWilliam both of Rye, NY preceded her in death.
Maggie was a devoted daughter, sister and aunt to Sophia Baskin (Brett Baskin), Peter Loferski, Charlie Metz, Cate McWilliam, Maddy, Julia & Anna O’Neill, and a great aunt to Beau Baskin.
Born in Rye and a proud New Yorker, Maggie was well known for her love of dance, art, food, travel, dogs, and yoga. She danced professionally with Harkness Ballet and was a teacher at the Rye Ballet Conservatory. While she considered herself a perpetual yoga student, she was also a gifted yoga teacher.
Small in stature, Maggie will always be remembered for her impeccable style, sweet tooth, quick wit, and big attitude. “Though she may be but little, she is fierce” (William Shakespeare).
A Memorial Mass will be held Thursday March 5, 2026 at 10 AM at Church of the Resurrection 910 Boston Post Rd, Rye, NY 10580. In lieu of flowers, Maggie requested donations to the FDNY Foundation.
