9. If neither parent is a British citizen, a child born here on or after 1 January 1983 will still be a British citizen if either the father or mother is legally settled. 'Settled’ means ordinarily resident (see paragraph 16) in the United Kingdom without being limited under the immigration laws as to how long the person can stay here. For this purpose, a person cannot be ordinarily resident if he or she is in breach of the immigration laws. We do not consider certain members of diplomatic or consular missions, or members of visiting forces or international organisations as being settled here, even if immigration control does not apply to them.
16. Whether a person is ordinarily resident or not depends on the facts of the case. A person who is not limited under the immigration laws to any restriction on the period for which he or she may remain is probably ordinarily resident if he or she:
a. has been living in the United Kingdom for a number of years, without being absent, except for short holidays; and
b. is in the United Kingdom legally (without being in breach of the immigration laws).
Long periods of absence from the United Kingdom (for more than a year, for example) may mean that a person is not ordinarily resident. Shorter periods of absence may also, in some circumstances, mean that a person is no longer ordinarily resident (for example, if he or she left the United Kingdom intending to live abroad permanently).