Section 22. An agent of the department shall visit each family foster home, not supervised and approved by a licensed placement agency, at least once a year and may be authorized by the department to remove a child to its care if in its judgment the welfare of the child or its protection from neglect or abuse so require. An agent who is refused such entry, or who is hindered in the removal of such child, may make complaint, on oath, to a justice of the court having jurisdiction, who may thereupon issue a warrant authorizing him to obtain sufficient aid, and at any reasonable time enter the building designated, and any part thereof, to investigate the treatment and condition of a child found there and to remove such child as herein provided. The department shall take such child temporarily into its care and forthwith notify the child’s parent or legal guardian, and shall, upon request, discharge such child to its parent or legal guardian. If the parent or legal guardian is unable or refuses to make suitable provisions for the child, the department shall make lawful provisions for its care under section twenty-three or twenty-four.