Question to the Home Office:

To ask the Secretary of State for the Home Department, if her Department will amend the official observations section of children's passports to allow a note when a holder's parent has a different surname to that of the child.

There are no plans to use the passport to identify parental relationships as
this would change the fundamental purpose of the document which is for
travel. Guidance on children travelling to the UK, including children
travelling with a parent who may have a different family name to the child, can
be found at:
https://www.gov.uk/government/publications/children-travelling-to-the-uk