Documents needed to send through post for British passport

[ukresident001]

Hi,
I have received the MN1 certificate for my child, and i applied for the first child passport.
HMPO has requested to send the original documents through post but I don't know which ones to send.
I would need to send British Citizenship Certificate, but what else is required?
Parents Marriage certificate? Child Birth Certificate?
Please advise.
Thanks

[CULLINAN]

The checklist will tell you what you need to send.

You only need to send:
Child’s foreign passport (if any).
Child’s registration certificate.
Child’s birth certificate.
Parent’s consent.

(all originals)