Hi,
Welcome to Ancestry Aid. I have to go out very soon, but will try to help you later if no-one else answers.
To start you off here's the reference for Frank's birth certificate which can be ordered here..............
General Register Office (GRO) - Official information on births, marriages and deaths
Name: Frank W Knowles Mother's Maiden Surname: Maltby Date of Registration: Jan-Feb-Mar 1930 Registration district: Nottingham Inferred County: Derbyshire Volume Number: 7b Page Number:
514
The certificate should name his father, or do know his name?