Princess Mary Adelaide Wilhelmina Elizabeth of Cambridge, later Duchess of Teck, was a member of the British royal family. She was one of the first royals to patronise a wide range of charities.
Mary Adelaide was the daughter of Prince Adolphus, Duke of Cambridge, and Princess Augusta of Hesse-Kassel. Her father was the seventh son of King George III and Queen Charlotte. Mary Adelaide married Francis, Duke of Teck, with whom she had four children. The Duke and Duchess of Teck's daughter, "May", was the wife of King George V and became known as Queen Mary. Through her daughter, Mary Adelaide was the grandmother of the British kings Edward VIII and George VI.