OPINION BY
MONTEMURO, J.¶ 1 This is an appeal from an Order delineating the legal and physical custody arrangements fashioned by the court for the parties’ minor child, a girl whose date of birth is February 3, 1993. Two provisions of the Order supply the basis for the instant appeal: the first directs that the child be raised in the Church of Jesus Christ of Latter Day Saints (Mormon), and the second prohibits Appellant/Father from teaching the child about polygamy, plural marriages, or multiple wives.
¶ 2 The parties, who are both converts to the Mormon faith, married in June of 1992 and divorced in February of 2001. Shortly thereafter, Appellant, who considers himself a fundamentalist because of his belief in polygamy, was excommunicated by the Mormon Church. In January of 2002, Appellant filed a complaint seeking joint physical and legal custody, eventuating in a conciliation and an interim order. After mediation failed to resolve the issues, the trial court received evidence and entered the order now under consideration. This appeal followed.,
¶3 In child custody cases, this Court’s review is of the broadest type, and will not result in reversal absent a finding that the trial court has abused its discretion. Tripathi v. Tripathi, 787 A.2d 436, 439 (Pa.Super.2001). Moreover,
[T]he appellate court is not bound by the deductions or inferences made by the *637trial court from its findings of fact, nor must the reviewing court accept a finding that has no competent evidence to support it. However, this broad scope of review does not vest in the reviewing court the duty or the privilege of making its own independent determination. Thus, an appellate court is empowered to determine whether the trial court’s incontrovertible factual findings support its factual conclusions, but it may not interfere with those conclusions unless they are unreasonable in view of the trial court’s factual findings[.]
McMillen v. McMillen, 529 Pa. 198, 602 A.2d 845, 847 (1992). Finally, “[i]t is well settled that the sole issue to be decided in a custody proceeding is the best interest and welfare of the child. This is determined on a case by case basis, considering all factors which legitimately impact upon the child’s physical, intellectual, moral and spiritual well-being.” Siliquini v. Kegel-Siliquini, 786 A.2d 275, 277 (Pa.Super.2001) (citations omitted).
¶ 4 In assigning error to the provisions of the custody Order concerning the teaching of polygamy and raising the child as a Mormon, Appellant argues that the trial court’s directives interfere with his constitutional right to unrestricted practice of his religion, and his right and duty as a father “to discuss the spiritual dimension of [the fundamentalist Mormon] life with his daughter.” (Appellant’s Brief at 20). In this regard he relies on Zummo v. Zummo, 394 Pa.Super. 30, 574 A.2d 1130 (1990), in which this Court established the standard by which the legal right of parents in custody situations to instruct their children in religious practices is to be measured. In Zummo we reaffirmed, inter alia, the long standing principle that “the court will not interfere with the religious preferences of either parent.” Tripathi, supra, at 440. Most critically, the Zummo court held that
to justify restrictions upon [a] parent’s right to inculcate religious beliefs in their [sic] children, the party seeking the restriction must demonstrate by competent evidence that the belief or practice of the party to be restricted actually presents a substantial threat of present or future physical or emotional harm to the particular child ... involved in [the] absence of the proposed restriction, and that the restriction is the least intrusive means adequate to prevent the specified harm.
Zummo, supra at 1157.
¶ 5 In addition to arguing the Order’s infringement of his rights, Appellant contends that the danger of harm to his daughter was insufficiently proven. Indeed, despite its findings that the practice espoused by Appellant is illegal, immoral, and illogical, and Appellant himself morally deficient, the trial court concluded that there was no evidence of a grave threat to the child.
¶ 6 However, the issue in this matter, stated in the most basic way, is whether a parent, by advocating a religious practice which is prohibited by law, poses a substantial threat to his child. We find that he does, and that no jurisprudence requires this Court to countenance the hazard posed merely because it occurs in the context of proselytism. As Appellee correctly points out, the United States Supreme Court, addressing the issue of polygamy in a series of cases, has held that First Amendment protections do not extend to immoral or criminal acts despite their sanction by religious doctrine. See Reynolds v. United States, 98 U.S. 145, 25 L.Ed. 244 (1878). Indeed, the Court has categorized even the advocacy of criminalized religious practices as itself a crime since, “to teach, advise and counsel their practice is to aid in their commission, and *638such teaching and counseling are themselves criminal and proper subjects of punishment, as aiding and abetting crime are in other cases.” Davis v. Beason, 133 U.S. 333, 347, 10 S.Ct. 299, 33 L.Ed. 637 (1890). Appellant has advanced no countervailing authority despite the antiquity of this ruling.
¶7 Moreover, unlike the situation in Zummo, where the parents were of differing but traditional religion beliefs and the issue was one of primacy, the conflict here does not involve competition or incompatibility between theological systems; the harm is not merely confusion or uncertainty produced by incompatible ideologies. Thus, the resolution in Zummo presents an imperfect analogue. Further, the orthodoxy or otherwise of Appellant’s beliefs is not before the court, nor is his constitutional right to hold those beliefs so long as he does not act on them; only the effects of his exposing a minor child to an illegal practice is being assessed. In this context, Appellant’s method of presentation is also worthy of note, given that he informed a wife candidate, his 14 year old stepdaughter, a witness whose testimony was accepted as true by the trial court, that she would “go to hell” unless she practiced what he preached. The question whether we would find similarly benign advocacy of drug abuse or child prostitution were they presented as foundational religious beliefs is no question at all.
¶ 8 As already noted, this Court has consistently recognized the moral and spiritual dimension involved in an award of primary custody. See also Boylan v. Boylan, 395 Pa.Super. 280, 577 A.2d 218 (1990); Wilder, Pa. Family Law Prac. and Pro., 3rd ed., § 28-13, at 321 (“It is appropriate for the court to consider religious practices in custody disputes because the child’s spiritual welfare is a consideration in custody cases.”) Thus, our province is not “[to] render[ ] a value judgment on the intrinsic truths of the various religious beliefs, but confine our investigation solely to any detrimental effect their practice may have on the development of the child.” Morris v. Morris, 271 Pa.Super. 19, 412 A.2d 139, 144 (1979) (emphasis added). Appellant’s promotion of his beliefs to his stepdaughter involved not merely the superficial exposure of a child to the theoretical notion of criminal conduct, but constituted a vigorous attempt at moral suasion and recruitment by threats of future punishment. The child was, in fact, warned that only by committing an illicit act could she comply with the requirements of her religion.
¶ 9 Appellant’s intent with his own daughter too, as the trial court clearly perceived from his testimony, is to inculcate in his child a belief in what he knows to be illegality. His instruction may perhaps, as the child matures, even become insistence that she engage in such conduct. The difference between the two involvements is vast, since the first, while undesirable, does not, unlike the latter, constitute indoctrination in a practice which the Commonwealth has determined to be criminal. Pennsylvania law, with its focus on the best interests of the child, does not obligate us to facilitate Appellant’s efforts.
¶ 10 The court’s factual findings as to the nature of the practice endorsed by Appellant and as to Appellant’s own character render its conclusion that Appellant poses no grave threat to his daughter both erroneous and unreasonable. However, the court’s solution, to prohibit the teaching of polygamy, is neither since it represents “the least intrusive means,” Zummo, supra, of implementing the court’s objective. Since we may affirm on any grounds, Espenshade v. Espenshade, 729 A.2d 1239, 1246 n. 5 (Pa.Super.1999), we approve the trial court’s Order on this point.
*639¶ 11 As for Appellant’s challenge to the trial court’s directive that the child be raised as a Mormon,1 his failure to advance any argument or cite any supporting authority on the subject enables us to deem the issue waived. Pa.R.A.P. 2119(a); Drum v. Shaull Equip. & Supply Co., 787 A.2d 1050, 1059 (Pa.Super.2001), appeal denied, 569 Pa. 693, 803 A.2d 735 (2002).
¶ 12 Accordingly, the trial court’s Order is affirmed.
¶ 13 Order affirmed.
¶ 14 JOHNSON, J. files a Dissenting Opinion.
. The child was baptized in the Church of Latter Day Saints.