If a child is under the age of 16 years, a relative who knows that another person is the lawful custodian of the child may not, with the intent to deprive the lawful custodian of the custody of the child: abduct, take, or carry away the child from the lawful custodian to a place within this State; having acquired lawful possession of the child, detain the child within this State for more than 48 hours after the lawful custodian demands that the child be returned; harbor or hide the child within this State, knowing that possession of the child was obtained by another relative in violation of this section; or act as an accessory to an act prohibited by this section.