Denis Charles Pratt was born in Sutton, Surrey, on 25 December 1908, the fourth child of solicitor Spencer Charles Pratt (1871–1931) and former governess Frances Marion Pratt (née Phillips; 1873–1960).1911 Census for England and Wales, The National Archives (findmypast.co.uk): RG number: RG14; Piece: 2929; Reference: RG14PN2929, RG78PN101; Registration District: Epsom; Sub District: Carshalton; Enumeration District: 7; Parish: Carshalton; Address: Wolverton, Egmont Road, Sutton; County: Surrey. His elder siblings were Katherine (1901–1976), Gerald (1902–1983) and Lewis (1907–1968). He changed his name to Quentin Crisp in his twenties after leaving home, and expressed a feminine appearance to a degree that shocked contemporary Londoners and provoked gay-bashing assaults.
