19 GCA § 5105: Continuing Jurisdiction.

(a) Where jurisdiction shall have been obtained by the Court in the case of any child, such jurisdiction shall be retained by the court for the purposes of this Chapter until such child becomes eighteen (18) years of age, unless he is discharged prior thereto by the court, or until the age of twenty-one (21) years if he has been committed to and received by any public institution or department or agency maintained by the government of Guam, or if the child is subject to an order of probation issued by the court; and the court may retain jurisdiction over a child placed by the court with such public institution or agency for temporary observation and care. Any decree or order of the court may be modified at any time, except as otherwise provided by law.

(b) Where jurisdiction shall have been obtained by the court through § 5103(a)(4) in the case of any child, such jurisdiction may be retained by the court until such child becomes twenty-one (21) years of age, unless he is discharged prior thereto by the court. Any decree or order of the court may be modified at any time, except as otherwise provided by law.

(c) With respect to any such child who becomes eighteen (18) years of age while under the jurisdiction of the court, and who has at such time been committed to a juvenile facility by the court, the court may, upon motion of Guam, the child, or upon its own motion, and after a hearing commit the child to the custody of the Director of Corrections for confinement in the adult facility, or in any suitable public institution, agency, or department. Any decree or order of the court may be modified at any time, except as otherwise provided by law.