 "Burke's Peerage" says that the grandson inherited Chatteris in 1839, after his maternal grandmother Jane had died that year.Although "A Genealogical and Heraldic Dictionary of the Landed Gentry of Great Britain" (1862) fails to mention Mr Dunn Gardner's parentage (as the eldest illegitimate son of a brewer John Margetts and his bigamous spouse Sarah Dunn-Gardner, Marchioness Townshend), it credits him with two surviving brothers (William and Cecil) and two sisters.The Townshend Peerage Case 1842-1843 gives details of all the children