I knew that Sandford KILBY (AFGs father) was living with his grandparents (the WORRINs) in 1851 but I could not trace his parents - who you now seem to have provided. Sandford was born at sea and I haven't found any written record.
The connection to York comes through the fact that AFG had links to two KILBY families - his father Sandford KILBY (whose antecedents I couldn't find) and also his mother Alice SCOTT who was the daughter of Henry SCOTT and Mary KILBY. Mary was the daughter of Thomas KILBY of York (b 1795). Alice and Sandford married in Calcutta in 1878.
I would be very interested in what info you have and will send you my research as soon as I can.