Maryan Stevens with her husband, retired Supreme Court Justice John Paul Stevens. (Courtesy of the Stevens family)

Maryan Stevens, a dietitian who was the wife of retired Supreme Court Justice John Paul Stevens, died Aug. 7 at a hospital in the Mount Vernon section of Fairfax County. She was 84.

She had complications following hip surgery, her husband said in a statement released by the Supreme Court.

Mrs. Stevens and her husband, who had once been neighbors in Chicago, were married in December 1979. It was the second marriage for both.

After moving to Washington, Mrs. Stevens worked as a dietitian at George Washington University Hospital.

Justice Stevens, who retired in 2010 after 35 years on the Supreme Court and is now 95, sometimes attributed his longevity to his wife’s dietary guidance.

“The most important key to my survival,” he said in 2011, “is the advice I’d give to everybody in the room: Marry a beautiful dietitian.”

Maryan Barbara Mulholland was born June 21, 1931, in Chicago. Her father was a real estate developer. She was a graduate of St. Mary’s College at Notre Dame, Ind.

Her first marriage, to Ron Simon, ended in divorce.

Survivors include her husband, of Arlington, Va., and Fort Lauderdale, Fla.; five children from her first marriage, Catherine Silver of Riverwood, Ill., Jerome Simon of Crystal Lake, Ill., Terrence Simon of Fort Lauderdale, Daniel Simon of Chicago and Caralyn Ross of San Diego; three stepdaughters, Kathryn Jedlicka of Downers Grove, Ill., Elizabeth Jane Sesemann of Clarendon Hills, Ill., and Susan Mullen of Arlington; 17 grandchildren; and 13 great-grandchildren.

A stepson, John J. Stevens, died in 1996.