Mary H. "Rosalie" Oster, a homemaker and volunteer, died in her sleep Tuesday at the Blakehurst retirement community in Towson. She was 97.
Mary Rosalie Eugenia Hammond was born at home in Roland Park and raised there and in Sparks. She was a 1926 graduate of Bryn Mawr School, where she played basketball and field hockey.
Mrs. Oster was the second-oldest living alumna of Bryn Mawr and was recently honored by the school, family members said.
Mrs. Oster earned a bachelor's degree in history in 1930 from Smith College, and after touring Europe, moved into a Bolton Hill boardinghouse owned by her mother.
She was working as a secretary at the U.S. Customs House in downtown Baltimore at the time of her 1938 marriage to Robert Wilson Oster.
Mr. Oster, who was a financial vice president and a director of United States Fidelity & Guaranty Co., died in 1979.
Mrs. Oster was a former board member of the Hammond Harwood House in Annapolis and the old Church Home and Hospital, and her philanthropic interests included Smith College.
She also was a fundraiser at historic Hampton Mansion near Towson, and helped secure a $1 million donation from Eli Lilly, the pharmaceutical executive, to help restore the mansion's orangerie.
In thanks for his generosity, Mrs. Oster provided genealogical data to Mr. Lilly on the mansion's former owners. His mother, Marie Ridgely Lilly, was a member of the Ridgely family that lived in the home from the late 1700s to the 1940s.
Mrs. Oster's brother, Hall Hammond, was a chief judge of the Maryland Court of Appeals. He died in 1991.
Mrs. Oster, formerly of Keswick Road, had lived at Blakehurst since the early 1990s.
She enjoyed spending summers at a family cottage on Summerland Island in the St. Lawrence River, and she continued her world travels until two years ago.
"She attributed her advanced age and good health to scotch, which she enjoyed every afternoon promptly at 5, and dark chocolate which gave her great pleasure," said her daughter, Rosalie O. Kerr of Boston.
Mrs. Oster was a communicant of the Episcopal Church of the Redeemer, 5703 N. Charles St., where a memorial service will be held in the chapel at 10:30 a.m. May 11.
Also surviving are two sons, Robert L. Oster of Ruxton and William H. Oster of Baltimore; seven grandchildren; three step-grandchildren; a great-granddaughter; and three step-great-grandchildren.