Mo. Rev. Stat. § 475.395

No person, other than a bank, trust company or public administrator shall be guardian of more than five wards at one time, unless all the wards are members of one family. Upon presentation of a petition by an attorney of the Veterans Administration or other interested person, alleging that a guardian is acting in a fiduciary capacity for more than five wards and requesting his discharge for that reason, the court, upon proof substantiating the petition, shall require a final accounting from such guardian and shall discharge him from guardianships in excess of five and forthwith appoint a successor.