 One of his few close companions was his niece Betsy ( Elizabeth Etty ) , fifth daughter of his brother John . Betsy was unmarried and 14 years younger than William , and became his housekeeper in 1824 . She remained in his service for the rest of his life , and as he grew older William increasingly came to depend on her , suffering distress whenever they were apart and regularly writing to her in panic whenever he did not hear from her . She became his companion and acted as his assistant , alongside his official assistant George Franklin . 
