My husband is a DAKE; his mother, Hilda L. Dake told him that about 5 generations back, in the Dake family there was a Fanny SLY, who was Cherokee. Might be a connection. Have you contacted Maurice DAKE, the official Dake/Deake family genealogist at dakehomedot com. It is free and a wealth of his and other's information. His research is extensive and might be able to help.