George Cotton married before 11 Nov 1637 Mary Onley, daughter of John Onley, Esq., of Catesby, Northamptonshire, by Jane, daughter of Thomas Pontesbury of Albrighton, Shropshire. They had one son, Richard, Esq., and four daughters. Georg is a descendant, through his maternal grandmother, of Magna Carta barons Richard de Clare, 3rd Earl of Hertford and his son Gilbert de Clare, 4th Earl of Hertford.
