OCI for U.K. Born child

Hi, I and my wife both are now British citizens and have OCI, we are applying for OCI for our newborn child, I have filled the online application form,
In the documents upload it mentions that in relationship documents we need to upload child birth certificate and further parents birth certificate!
Neither of us have our birth certificate, we do have our passports, OCI and also Indian passport surrender certificates. Will that be sufficient or we may have some issues getting OCI for our child? Please advise. Thanks

For other benefit, we submitted OCI application for our child. Birth certificate of the child is required, but birth certificate of parents is not required, which will be required if applying onthe basis of GRAND parents India origin, I hope that helps.