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To be a guardian of a child is to have a legal obligation to care for and maintain the child, usually until the age of 16. This rights and obligations of guardianship are usually associated with those of custody (see: Custody of children). In normal circumstances the child's parents exercise joint guardianship. In the event of the death of a parent, this passes to the survivor. In the event of the deaths of both parents, guardianship may pass to a person nominated in the wills of the parents. Otherwise, another person -- often a relative -- may make an application to the court for guardianship. In cases of divorce (see: Divorce) guardianship may be a matter for a court to decide. If guardianship is not asserted by anyone, the child may be made a 'ward of court', and a guardian appointed by the court. In some cases a parent may be made a guardian, but under the control of the court.