The status of children born abroad is in line with that of the
less-privileged parent.
The child is expected to have ILR (typically acquired at the same time as the less privileged parent) before applying for citizenship using Form MN1. The expectation is that either both parents are British citizens or one is a British citizen and the other one is on ILR and applying for citizenship at the same time.
Also see the points listed on Pages 13-14 of
Guide MN1 for other things that the Home Office looks for when granting registration under Section 3(1).
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