Immigrationboards.com

have received citizenship approval letter and wish to apply for passport after ceremony.

having looked through the booklet, do i need to obtain fathers birth cert. and parents marriage cert. as well.

if so, i don't think they will have either of these documents.
will this cause problems for me.?

do i need to obtain fathers birth cert. and parents marriage cert. as well.

No.

The booklet explains clearly what is required if you have Naturalised as British. Note that the same form is used for everyone, those born British and those who applied for citizenship. Submit only what the 'naturalisation' section tells you to.