She is Georges second wife, after his first wife Susanna dies in 1832. Her birth detail comes from the 1861 census, which could be entirely wrong.
Sarah married Yeoman George Cumbers, son of William Cumbers and Ann. (Yeoman George Cumbers was born in 1798 in Romford and died on 28 Dec 1858 in South Weald.)
George and Sarah are both widows.