What is the test for appointing a guardian ad litem for a minor?

that person shall appear . . . by a guardian ad litem appointed by the court in which the action or proceeding is pending, or by a judge thereof, in each case. . . . The . . . guardian ad litem so appearing for any minor . . . shall have power, with the approval of the court in which the action or proceeding is pending, to compromise the same, to agree to the order or judgment to be entered therein for or against the ward or conservatee, and to satisfy any judgment or order in favor of the ward or conservatee or release or discharge any claim of the ward or conservatee pursuant to that compromise." (Italics added.) Pursuant to that statutory requirement, "[o]nce a guardian ad litem is appointed, the action may not thereafter be compromised, settled or dismissed without court approval, thus insuring the interests of the child have been fully and fairly considered." (County of Shasta v. Caruthers (1995) 31 Cal.App.4th 1838, 1847.)