Sec. 1. As used in this chapter, "child" means a person who:
(1) is less than eighteen (18) years of age;
(2) is at least eighteen (18) years of age at the time a complaint is made but was less than eighteen (18) years of age at the time of the alleged act or omission that is the subject of the complaint; or
(3) is at least eighteen (18) years of age but has been under the continuing jurisdiction of a juvenile court based upon an informal adjustment, child in need of services action under IC 31-34, or termination of parental rights action under IC 31-35 since becoming eighteen (18) years of age.