Hi, I dont know of the William you mentioned but I am also researching the Fack's from Bottosham, Cambridge. My 7 Great grandmother was Ann Flack born in 1724 in Swaffham, Cambridge. She had a daughter Amy Flack. Ann died in 1801 in Bottisham, Cambridge. Ann's parents were John Flack and Ann Amy. John also died in Bottisham, Cambridge.