You can apply to get your child returned from a Hague Convention country if:
the child is under 16 years of age
the child was living in New Zealand at the time they were taken overseas
you have ‘rights of custody’ to the child (legal guardianship) and you were exercising your rights of custody at the time the child was taken overseas (even if you don’t have day-to-day care of your child, you may still have rights of custody)
your child was taken or kept overseas without your agreement or the agreement of the court.