Applying first child passport for 3 month old son

Hi.

My wife is on the spouse visa and we had a baby 3 months ago.
Im applying for his first passport.
I am british born but shes a pakistani national.
Now the grandparents bits i can skip i have been told but apart from my sons biryh certificate do i only send my birth certificate or my passport too?

These are the documents i need to send.
Applicant’s documents
Send the following:

full birth or adoption certificate

Parents’ documents
For 1 of your parents, send 1 of the following:

full birth or adoption certificate
naturalisation or registration certificate
the non-British passport they had when you were born showing indefinite leave to remain
Grandparents’ documents
Send all of the following for both maternal grandparents:

full birth or adoption certificate
grandfather’s marriage certificate to your grandmother (if this applies)
And all of the following for both paternal grandparents:

full birth or adoption certificate
grandfather’s marriage certificate to your grandmother (if this applies)