(1) A child shall be a qualified child (in this Part referred to as "a qualified child") for the purposes of child benefit where -

(a) he or she is under the age of 16 years, or

(b) having attained the age of 16 years he or she is under the age of 19 years and -

(i) is receiving full-time education, the circumstances of which shall be specified in regulations, or

(ii) by reason of physical or mental infirmity, incapable of self-support and likely to remain so incapable for a prolonged period,

and

(c) he or she is ordinarily resident in the State, and

(d) he or she is not detained in a children detention school and is not undergoing imprisonment or detention in legal custody.

(2) Notwithstanding subsection (1)(c), a child who resides with a qualified person and that person's spouse, civil partner or cohabitant while the qualified person or that person's spouse, civil partner or cohabitant -

(a) being a member of the Defence Forces or a civil servant in the civil service of the Government or the State, is in the service, outside the State, of the Government, the State or an international organisation,