Mo. Rev. Stat. § 211.231: Indeterminate commitments, exception — exchange of information by court and institution or agency.

1. All commitments made by the juvenile court shall be for an indeterminate period of time, unless the child is committed pursuant to subdivision (3) of subsection 3 of section 211.181, and shall not continue beyond the child's twenty-first birthday.

2. Whenever the court commits a child to an institution or agency, it shall transmit with the order of commitment a summary of its information concerning the child, and the institution or agency shall give to the court such information concerning the child as the court may require from time to time so long as the child is under the jurisdiction of the juvenile court.