Indefatigable Mary Wilson (Mrs. Henry B.) Thompson of Wilmington was an activist in many causes: children's health, education, Red Cross, Association Opposed to Woman Suffrage, Anti-Prohibition, and historic preservation. She had a vague memory of visiting Rehoboth with her grandparents in 1872, when it was virtually uninhabited and an unspoiled paradise. When she built here in the 1920s, the village was rather seedy, but she soon saw to that, telling the 1932 edition of Who's Who that she had “improved Rehoboth Ave., planted and designed the gardens throughout the town.” She bought a piney lot from Irénée du Pont well away from the beach with its undesirable surf-noise, wind, damp, and glare. She took great pride in designing her home herself. She visited old houses in Sussex County, taking photographs, and finally settled on one in Lewes as a model. A “young architect” drew up the specifications—no doubt her son, Jim, then an architecture student at Princeton. The two-story, shingled Mon Plaisir with its dormer windows was meant to recall architecture of the 1790s and was fully paneled inside with pine. Screened French doors opened onto enormous porches.