Defendant, Val Franklin Stone, appeals from an order denying his petition in proceedings supplemental to a divorce to deprive plaintiff of custody of their children and award them to him.
The parties were married in 1952. In 1964, after 12 years of marriage and the birth of four children, then ages 11, 8, and twins 5, the plaintiff was awarded a decree of divorce, custody of the children and $50 each for their support. Two years later in 1966, the defendant initiated this proceeding requesting the court (1) to hold plaintiff in contempt for failure to honor his visitation privileges, (2) to deprive her of custody and award the children to him, and (3) to require the plaintiff to have a mental examination.
After a pretrial conference had framed those issues, a plenary trial was had on .June 14 and 15, 1966, as a result of which the court found in favor of the plaintiff on each issue, i.e., (1) that she was not in contempt for refusal of defendant’s visiting rights; (2) that she was neither mentally incompetent nor otherwise unfit to •have the custody of the children; and (3) *380that there was not a sufficient showing to justify ordering her to submit to a mental examination. As to the latter issue he added this, “However, the plaintiff should be closely observed, and if it appears at some future time that a psychiatric and physical examination is necessary, application to the court shall be made immediately.”
In reviewing the trial court’s order in divorce proceedings there are certain well established principles to be borne in mind. The findings and order are endowed with a presumption of validity, and the burden is upon the appellant to show they are in error. Even though our constitutional provision, Section 9 of Article VIII, states that in equity cases this court may review the facts, we nevertheless take into account the advantaged position of the trial judge. Accordingly, we recognize that it is his prerogative to judge the credibility of the witnesses, and in case of conflict, we assume that 'the trial court believed the evidence which supports the findings. We review the whole evidence in the light most favorable to them; and we will not disturb them merely because this court might have viewed the matter differently, but only if the evidence clearly preponderates against the findings.
For similar reasons, the trial court is allowed a comparatively wide latitude of discretion in determining what order should be made in such matters; and we-will not upset his judgment and substitute-our own unless it clearly appears that the-trial court abused its discretion, or misapplied the law. The following are a few examples of innumerable cases supporting-the principles just stated: Slaughter v. Slaughter, 18 Utah 2d 274, 421 P.2d 503; Dahlberg v. Dahlberg, 77 Utah 157, 292 P.2d 214; Hendricks v. Hendricks, 91 Utah 553, 63 P.2d 277; Anderson v. Anderson, 104 Utah 104, 138 P.2d 252; Allen v. Allen, 109 Utah 99, 165 P.2d 872; Alldredge v. Alldredge, 119 Utah 504, 229 P.2d 681, 34 A.L.R.2d 305 (1951); Pinion v. Pinion, 92 Utah 255, 67 P.2d 265.
The charge that the trial court erred in refusing to order the plaintiff to have a psychiatric examination injects into this case an unusual issue which requires special comment. Defendant’s contention is based on Rule 35(a), U.R.C.P., which provides:
(a) Order for Examination. In an action in which the mental or physical condition of a party is in controversy, the court in which the action is pending may order him to submit to a physical or mental examination by a disinterested and impartial physician. The order may be made only on motion for good cause shown and upon notice to the party to be examined and to all other parties and shall specify the time, place, manner, conditions, and scope of the examination *381and the person or persons by whom it is to he made.
This rule was initiated primarily for use in personal injury cases. Yet it must be conceded that by its language it applies to any action in which the mental or physical condition of a party is in controversy. However, the important point is that it is not mandatory, as the position of the defendant seems to imply. Its language shows clearly and unequivocally that it was intended to be discretionary. This was undoubtedly made so designedly, and this is particularly desirable because mental examinations may be involved.
The question of a person’s sanity nearly always involves considerable delicacy. If mere allegations in an affidavit compelled the court to require a party to submit to a psychiatric examination, a way would be open for opposing parties to harass, annoy or intimidate each other. The potential for mischief in such a situation is obvious and the court would always be well advised in exercising caution and restraint in regard to such a request, as it appears was done here.
While there is some evidence that the plaintiff had at times been somewhat erratic in her behavior, there is countervailing evidence that the mental and/or nervous difficulties she suffered from had been temporary, and that she was a good mother to her children. The capstone on this point is that upon disputed evidence, the trial court made an affirmative finding that she was not mentally incompetent nor otherwise unfit to care for them. The concern for their welfare in including in the order the provision that if in the future there should be evidence of need for a psychiatrist that should be immediately called to the attention of the court is commendable. In proceedings supplemental to the divorce, the choice of the older children as to parental custody is advisory only. See Anderson v. Anderson, 110 Utah 300, 172 P.2d 132.
It is our opinion that adherence to the principles hereinabove discussed impels the conclusion that the trial court did not abuse his discretion either in refusing to order the mental examination or in refusing to modify the decree. His action is therefore affirmed. Costs to plaintiff (respondent) .
CALLISTER and TUCKETT, JJ., concur. HENRIOD, J., concurs in the result.