Down House is the former home of the English naturalist Charles Darwin and his family. It was in the house that Darwin worked on his theories of evolution by natural selection. It is now a museum. They moved in on the 14 September 1842. The Darwin family then consisted of Charles, his wife Emma and their children William Erasmus and Anne. Emma was heavily pregnant with Mary Eleanor, who was to be born on 23 September but to die less than a month later on 18 October. Also the other Darwin children would be born here: Etty, George, Bessy, Francis, Leonard, Horace and Charles Waring Darwin. The Darwins had ten children: two died in infancy. The death of his 10 year old daughter had a devastating effect on Darwin. Whenever they fell ill he feared that they might have inherited weaknesses from inbreeding due to the close family ties he shared with his wife who was also his cousin. Charles Darwin died at the house in 19 April 1882, aged 73. Emma also died there in 1896. The house is proposed to become a World Heritage Site.