An employee is entitled to eighteen weeks’ leave in respect of any individual child.

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Where the period for which an employee is normally required, under his contract of employment, to work in the course of a week does not vary, a week’s leave for the employee is a period of absence from work which is equal in duration to the period for which he is normally required to work.

Where the period for which an employee is normally required, under his contract of employment, to work in the course of a week varies from week to week or over a longer period, or where he is normally required under his contract to work in some weeks but not in others, a week’s leave for the employee is a period of absence from work which is equal in duration to the period calculated by dividing the total of the periods for which he is normally required to work in a year by 52.

Where an employee takes leave in periods shorter than the period which constitutes, for him, a week’s leave under whichever of paragraphs (2) and (3) is applicable in his case, he completes a week’s leave when the aggregate of the periods of leave he has taken equals the period constituting a week’s leave for him under the applicable paragraph.