As used in this chapter, unless the context requires otherwise:

    (a) "Person in loco parentis" means a person who is not the parent or guardian of a minor, but who has either legal custody of a minor or physical custody of a minor and is providing support and care for the minor.

    (b) "Suitable for hospitalization" means a determination concerning a minor that all of the following criteria are met:

    (i) The minor is a minor requiring treatment.

    (ii) The minor is in need of hospitalization and is expected to benefit from hospitalization.

    (iii) An appropriate, less restrictive alternative to hospitalization is not available.