[1a] The guardian ad litem and her attorneys were without power to enter into and the court was without power to approve the stipulation. Section 196a of the Civil Code provides that a civil suit in behalf of a minor illegitimate child to enforce the obligation of a parent to support it may be maintained by a guardian ad litem and in such action the court has power to order and enforce the performance of such obligation. The power of a guardian ad litem in such an action is not unlimited. [2] In effect the court is the guardian, and the person named as guardian ad litem is an officer of the court appointing him and is the agent of the court. "He is like an agent with limited powers." (Cole v. Superior Court, 63 Cal. 86, 89 [49 Am.Rep. 78].) A minor, who must of necessity appear by his guardian, is not bound by the admissions of the guardian which mean the sacrifice or giving away of the ward's property. (Kidwell v. Ketler, 146 Cal. 12, 18 [79 P. 514]. See, also, Waterman v. Lawrence, 19 Cal. 210, 217 [79 Am.Dec. 212].) The relationship between a guardian ad litem or the attorney whom he employs and the minor is not the same as that between an attorney and an adult client. It is the duty of the guardian and the attorney to protect the rights of the minor, and it is the duty of the court to see that such rights are protected. The court may set aside or disregard concessions of the guardian which have not already been judicially approved and which are shown to the court to have been improvidently made. Any acts or concessions that apparently waive or surrender any material right of the minor, such as the right to a trial, should be set aside unless they be shown to be beneficial or, in any event, not prejudicial to the rights and interests of the minor. (Eidam v. Finnegan, 48 Minn. 53 [50 N.W. 933, 934, 16 L.R.A. 507].) The appointment of a guardian ad litem is not a bare technicality and the *658 office of guardian involves more than perfunctory or shadowy duties. It is the duty of a guardian ad litem to protect or defend a suit, as the case may be. The guardian ad litem can neither admit anything against nor waive anything in favor of his ward, but the adversary of the infant must be required to prove his whole case. (Greene v. Mabey, 35 R.I. 11 [85 A. 118, 120]; Spotts v. Spotts, 331 Mo. 917 [55 S.W.2d 977, 983, 87 A.L.R. 660].)