Hi, I am Philip Castleman from Sydney Australia, and am descended from Jemmets from Henley on Thames. I am unclear of the connection with the Faversham Jemmets. In 1881 census is Emily Jane Jemmet, b c 1864. Her father on her Marriage cert to Walter Castleman at Reading in 1885 was John Jemmet, a brewer, who was already deceased. There is a listing for a widow, Caroline Jemmet (living West Hill at Henley), who may be John's wife, as he was deceased at the time of the 1885 wedding. There is also a John Jemmet b 1804, also at West Hill Henley, who may be Emily's grandfather. Do these possibly link with your line?
Philip