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Caseworker guidance for Registration as British citizen: children wrote:Children applying in line with their parents

We recognise that a number of children apply for registration under section 3(1) at the same time as their parents apply for naturalisation. Such children have usually been living in the UK with the parents and have completed a period of lawful residence.

You must normally register where:

one parent is a British citizen or about to become one through registration or naturalisation
the other parent (if involved in the child’s life) is a British citizen or settled in the UK
the child has been resident in the UK for the last 2 years - (if the child is under the age of 2 you can accept a shorter residence period, taking into account the age of the child)
the child is settled in the UK
where necessary both parents consent to the registration or any objections by the non-applying parent are ill founded
there is no reason to refuse on character grounds

Registering exceptionally under section 3(1)
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Child’s future intentions
You must be satisfied that a child’s future is clearly seen to lie in the UK before you register them under this provision.

You should normally accept that a child’s future lies in the UK where this is stated in their application unless there is information to cast doubt on this, such as:

the child, or one or both of their parents, has recently left the UK for a period of more than 6 months
the child is about to leave the UK
one or both parents are resident abroad