I'm not a lawyer, but reading the Children and Young Persons (Care and Protection) Act 1998 - my guess would be she would have to be 25 to be identified as the child, not sure about ID'ing herself - IMO
View - NSW legislation
(1AA) The name of a child or young person who is or has been under the parental responsibility of the Minister or in out-of-home care must not be published or broadcast in any form that may be accessible by a person in New South Wales, in any way that identifies the child or young person as being or having been under the parental responsibility of the Minister or in out-of-home care (however expressed).
Note—
Identifying the child or young person as being or having been a foster child or a ward of the State, or as being or having been in foster care or under the parental responsibility of the Minister, or in the care of an authorised carer, are all examples of identifying the child or young person as being or having been in out-of-home care.
(1A) The prohibition in subsection (1) or (1AA) applies to the publication or broadcast of the name of the child or young person concerned until—
(a) the child or young person attains the age of 25 years, or
(b) the child or young person dies,
whichever occurs first.