OPINION
James M. Dowd, JudgeCorey Miller (“Father”) appeals from the trial court’s judgment’ granting Respondents Troy Ritter (“Great-Uncle”) and Melinda Ritter’s (“Great-Aunt”) (collectively “Respondents”) petition for letters of guardianship and' conservatorship of Father’s three-year-old son, L.M. (“Child”). Father raises two points on appeal: 1) that the trial court misapplied section 475.030.4(2),1 the applicable section of Missouri’s guardianship law; and 2) that the trial court’s finding that Father is unfit is not supported by substantial evidence and is against the weight of the evidence. Because we find that the trial court misapplied the law and that the judgment is unsupported by substantial evidence, we reverse.
Facts and Procedural History
Child was born on October 4, 2012, to Father and Respondents’ niece, Brooke Moore (“Mother”). During the early months of Child’s life, Respondents voluntarily provided substantial babysitting assistance.
In April 2013, with Great-Aunt’s assistance, Mother initiated a paternity action against Father , in Marion County. Father did not contest his paternity of Child. By agreement of the parties, Respondents were allowed to intervene. The parties reached an agreement calling for Father and Mother to be awarded joint legal custody with Father to have sole physical custody subject to’ Mother’s visitation rights pursuant to a parenting plan. The parties’ agreement further called for Respondents to be allowed to exercise Mother’s visitation rights if Mother failed to do so. On July 10, 2013, the court entered its judgment and parenting decree which approved the parties’ above-described, agreement.
Thereafter, Mother’s visitation was sporadic at best and Respondents exercised Mother’s visitation as- permitted by the parenting plan. Father, for his part, maintained physical custody of Child. On certain occasions ■ after September 2013, Father left Child with "Respondents beyond the time' set forth'in the parenting *213plan. During a portion of that time, - at least three months, Respondents charged Father on a weekly basis for their child care services. Father continued to exercise custody over Child and continued, to provide for him financially, including by maintaining health insurance for Child.
From at least April 2014 until the August 2014 trial, Father' followed the custody and visitation schedule set forth in the parenting plan. Child went to daycare four days a week. While Father was at work and Child was not at daycare, Father’s girlfriend and Father’s family members cared for Child.
On April 16, 2014, Respondents filed the petition at issue on this appeal in Ralls County.2 The petition alleged that Father and Mother were unable and/or unwilling to be Child’s guardians and conservators,3 Mother consented to the appointment of Respondents as guardians and conservators of Child. Father opposed the petition. The trial court appointed a guardian ad litem (the “GAL”) to represent Child in connection with the petition.
The matter went to trial on August 20, 2014. The court took judicial notice of the paternity action mentioned above. Mother did not attend the hearing and Father’s attorney informed the court that he had been unable to locate her. The court heard testimony from the parties and from the GAL who testified that he did not find Father to be an unfit parent.
On October 3, 2014, the court issued its judgment, granting Respondents’ petition. The court found that Respondents possessed more stability in their lives than Father and that Respondents’ past behavior exemplified a more stable' life than Father’s. The court found that Father’s lifestyle and circumstance were not conducive to a stable environment. The court noted that Father had been in at least three relationships since Child was born, including one with Mother, and had moved in with his current girlfriend after a very short period of time. The court concluded that Child had more stability in his life when he was with Respondents than when Child was with Father and found Child’s best interests were served by placing his custody with Respondents. The court concluded as a result of this comparison between Respondents and Father, that both Father and Mother were unfit.* Nevertheless, the court found that-Child’s best interests required Father to be allowed substantial, unsdpervised visitation with Child. This appeal follows.
Standard of Review
The trial court’s judgment in guardianship proceedings is to be affirmed *214unless it is unsupported by substantial evidence, is against the weight of the evidence, or erroneously declares or applies the law. In Matter of J.D.D., 450 S.W.3d 836, 840 (Mo.App.E.D. 2014); Blakely v. Blakely, 83 S.W.3d 537, 540 (Mo.banc 2002). A claim that there is no substantial evidence to support the judgment or that the judgment is against the weight of the evidence necessarily involves review of the trial, court’s factual determinations, and a court will only overturn a judgment under these fact-based standards of review when the court has a firm belief that the judgment is wrong. Pearson v. Roster, 367 S.W.3d 36, 43 (Mo.banc 2012). Due regard is given to the trial court to judge the credibility of the witnesses. In re Estate of A.T., 327 S.W.3d 1, 2 (Mo.App.E.D. 2010).
We apply de novo, review, however, to questions of law decided in court-tried cases. Pearson, 367 S.W.3d at 43. Statutory interpretation is an issue of law that this court reviews de novo. Blakely, 83 S.W.3d at 540. When presented with an issue of mixed questions of law .and fact, we defer to the trial court’s factual findings so long as they are supported by competent, substantial evidence, but review de novo the application of the law to those facts. Pearson, 367 S.W.3d at 44.
Discussion
A. The interest of a parent in the care, custody, and control of a child is perhaps the oldest of the fundamental liberty interests recognized by the United States Supreme Court.
At the outset of our analysis, we are guided by certain fundamental constitutional principles governing the rights of parents as acknowledged by the United States Supreme Court and recently recognized by this court in T.W. ex rel. B.W. v. T.H., 393 S.W.3d 144, 147-48 (Mo.App.E.D. 2013):
The Fourteenth Amendment to the United States Constitution provides that no State shall “deprive any person of life, liberty, or property, without due process of law.” The United States Supreme-Court has long recognized that the Fourteenth Amendment’s Due Process Clause, like its Fifth Amendment counterpart, guarantees more than fair process.* Troxel v. Granville, 530 U.S. 57, 65, 120 S.Ct. 2054, 147 L.Ed.2d 49 (2000) (plurality opinion). The Clause includes a substantive component, providing greater protection against government interference with certain fundamental rights and liberty interests. Id. -The liberty interest at issue in this case — the interest of a parent in the care, custody, and control of her child— is perhaps the oldest of the fundamental liberty interests recognized by the United States Supreme Court. Id.
B. Missouri’s guardianship statutes
With this constitutional backdrop, we turn to' Missouri’s statutory framework govérning the issues in this case. There are three principal statutes that govern the guardianship of a minor. In re Estate of A.T., 327 S.W.3d at 2 (citing Flynn v. Flynn, 34 S.W.3d 209, 211 (Mo.App.E.D. 2000)). Section 475.025 provides that the father and mother are the natural guardians of their children and have “the custody and care of their persons and education.” Section 475.030.4(2) authorizes the court to issue letters of guardianship over a minor in three circumstances, including, as is relevant here, where the parent or parents are unwilling, unable, or adjudged unfit to assume the duties of guardianship. Section 475.045.1 provides that the parent or parents of a minor shall be appointed as guardians except where the parent or-parents are adjudged unfit *215for those duties, waive their rights to be appointed, or when letters of guardianship and conservatorship are issued pursuant to section 475.030. Section 475.045.3 provides that if no parent is appointed under, subsection 1 of this section, the court shall appoint as guardian or conservator, the most suitable person who. is willing to serve and whose appointment serves the best interest of the child to a stable and permanent placement.
Reading these statutes together, a court should not appoint a guardian for a child unless there is no parent available, willing, and able to care .and provide for the child. In re Estate of A.T., 327 S.W.3d at 2 (citing Flynn, 34 S.W.3d at 211). Importantly, these statutes create a rebut-table presumption that a parent is the. appropriate custodian for his or her child. In re Estate of A.T., 327 S.W.3d at 2 (citing Cotton v. Wise, 977 S.W.2d 263, 264 (Mo.banc 1998)). That presumption can be overcome, however, if there is sufficient evidence presented that the parent is unfit, unwilling, or unable to take charge of the child. In the Matter of J.D.D., 450 S.W.3d at 841.
Missouri law allows for the appointment of a guardian over a minor as a stop-gap measure to provide for the care and custody of a minor for the period of time when the parent is unable, unwilling, or unfit to perform his or her parental functions. See Flathers v, Flathers, 948 S.W.2d 463, 468 (Mo.App.W.D. 1997). However, we are mindful that an order of guardianship can have the effect of terminating the parental right of custody to a child. See Piedimonte v. Nissen, 817 S.W.2d 260, 269 (Mo.App.W.D. 1991) (noting that the effect of the guardianship order was to terminate the parental right of custody on a finding of ordinary neglect). Given that an order of guardianship can abrogate or abridge the rights of parents, the standards provided by the guardianship statutes must be followed. See Cotton, 977 S.W.2d at 265.
Once a parent has been found unfit in a guardianship proceeding, the burden of proving that the parent is fit to assume custody of a child shifts to the parent and the statutory presumption in favor of the parent as the custodian is removed. In re Estate of Moreau, 168 S.W.3d 548, 551 (Mo.App.S.D. 2005). To terminate the guardianship of a third party, the burden of proof -is on the parent to prove by a preponderance of the evidence that the parent is fit, suitable, and able to assume the duties of guardianship and that it' is in the best interest of the minor that the guardianship be terminated. See § 475.083.2(3), 6; In re Schnieders, 178 S.W13d 632, 634 (Mo.App.W.D. 2005). A parent can only file a petition to terminate guardianship once every 180 days. § 475.083.6: •
C. The presumption in favor of parents versus third parties in connection with the guardianship of their children.
The presumption in favor of parents as a child’s guardians is rooted in fundamental liberty interests founded in the United States and Missouri constitutions. See Troxel, 530 U.S. at 65, 120 S.Ct. 2054; T.W. ex rel R.W., 393. S.W.3d at 147-48,; § 475.045. In Missouri, a parent does not stand on equal legal footing with a third party in the context of the guardianship of the child. § 475.045. The parent is entitled to the presumption that the parent is the appropriate custodian for his or her child until this presumption is rebutted and the statutes allowing a parent to be stripped of the right to .the. custody of his or her child must be followed.
This principle was illustrated by the Missouri Supreme Court in Cotton v. Wise, 977 S.W.2d 263 (Mo.banc 1998).- In Cot*216ton, the trial court granted the petition for guardianship filed by an older half-sister on behalf of her two younger half-sisters over the father’s objection. The Supreme Court reversed, holding that the trial court misapplied Missouri’s guardianship law when it compared the parents with the third party (older half-sister) as if they were equals under the law in order to determine what was in the best interests’ of the children. Id. at 264-66.
The Court noted that the record was replete with references to the father’s deficiencies as a parent and that “[t]he record supports the trial court’s conclusion that granting custody to [half-sister] is in, the children’s best interest.” Id. at 264. The Court concluded, however, that under the guardianship statute, the question was not which party.better served the children’s best interest. Id. Rather, when one of the parties was the children’s parent, the question was whether the parent was “unwilling, unable or adjudged to be unfit to assume the duties of guardianship.” Id. In this regard, the trial court had misapplied the \sm.
The Co'urt rejected sister’s arguments that the trial court’á extensive discussion óf father’s shortcomings suggested that he was unfit, unable, or unwilling to care for the children or that the trial court’s decision granting her'guardianship amounted to such a finding. Id. The Court suggested that while the trial court’s recitation of facts was “some proof’ that father was unfit, unable, or unwilling to care for his children, there must be a finding that the parent is unfit, unable, or unwilling to care for his children. Id. This determination must be made “in the first instance” based on the evidence and due regard' to the presumption in favor of the parent. Id. And the determination should be based not only on present circumstances, but on the parent’s history of. dealing -with the children. Id. (citing Reece v. Reece, 890 S.W.2d 706, 710-11 (Mo.App.W.D.1995)).
D. The trial court misapplied the guardianship statute because the court’s finding of unfitness on the part of Father and award of guardianship to Respondents resulted entirely from the court’s comparison of the relative merits of Father with those of Respondents.
A review of the court’s analysis demonstrates that the court failed to follow the guardianship statutes and the reasoning and holding in Cotton. The court relied heavily on In re Moreau v. Royster, 18 S.W.3d 447, 449 (Mo.App.S.D. 2000), for the proposition that in a contest between a parent and a third party, a finding of “unfitness” could be made by comparing the relative merits of a parent'with a third party. This approach was rejected recently in In re Estate of L.G.T. v. N.R., 442 S.W.3d 96, 112 (Mo.App.S.D. 2014), where the court held that the determination of parental unfitness may not be made by comparing the relative merits of the parent with those of a third party seeking the guardianship over the child. We agree.
This is because under section 475.030.4(2), the determination of unfitness must be made in the first instance by the trial court after reviewing all the evidence and giving due regard to the presumption in favor of the parent and the question of a child’s best interest is not reached unless the trial court has found the parent to be unwilling, unable or adjudged unfit to assume the duties of guardianship. Cotton, 977 S.W.2d at 264-65; In re Estate of L.G.T., 442 "S.W.3d at 111; See also In re Estate of A.T., 327 S.W.3d at 2 n. 3.
Here, the trial court erred in declaring and applying the law by considering Child’s best interests as between Father and Respondents before first determining whether Father was fit *217to be Child’s guardian. At this stage of the inquiry, the trial court had to independently determine Father’s fitness to be Child’s guardian in light of the presumption that Father is Child’s appropriate custodian. Cotton, 977 S.W:2d at 264. The essence of the trial court’s judgment, however, is that the court believed Respondents would provide Child more stability. ..The court should not have considered this without first making an independent determination regarding Father’s fitness to be Child’s guardian. Because the trial court did not make this determination first and independently of the best interests of the child analysis, the judgment must be reversed.
E. Respondents failed to overcome the presumption that Father is Child’s appropriate custodian and the court’s finding of unfitness on the part of Father is unsupported by substantial evidence.
, In order to overcome the presumption that Father is the appropriate custodian of Child, Respondents were required to present evidence showing that Father was unfit, unwilling, or unable to take charge of - Child. In the Matter, of J.D.D., 450 S.W.3d at 841. In determining a parent’s fitness to serve as a child’s guardian, courts have considered the stability in a parent’s life, the care the parent would be able to provide on a daily basis, the environment in which the child would be raised, the amount of effort made by the parent to furnish any financial support, and the parent’s mental health. See id. at 842. Another factor that may be considered is the moral environment to which the child will be subjected, but the analysis is not about condemnation nor approval of a moral standard. See Massman v. Massman, 784 S.W.2d 848, 849 (Mo.App.E.D. 1990). Rather, the issue is whether the conduct is detrimental to the child’s welfare and there must be evidence that the parent’s conduct 'has had or will have an adverse impact on the child'. Id. Finally, whether a parent is unfit must be based on existing conditions,- but past conditions may illuminate the understanding of present conditions.- In re Estate of L.G.T., 442 S.W.8d at 112. .
Here, there is no substantial evidence in thé record to support a finding that Father is unfit; Indeed, wé find that the reasons the trial court set forth for finding Father unfit are insufficient as a matter of law. The court' noted that since the birth of Child, Father has been in at’ ’least three relationships, had been in a relationship with Mother even after a safety plan was set up by the Children’s- Division, and chose to move in with his current girlfriend after a very short period of tibie. However, there was no evidence that any of Father’s past relationships had any adverse impact on Child and the evidence shows that since at leást February 2014, Father has been in one relationship with his current girlfriend with whom he has been living since that time. Given that the evidence shows that Father provides Child with adequate care and- there was no evidence that any of Father’s past or current relationships had any negative- impact on Child, we find that Father’s conduct in this regard is insufficieht to support a finding of unfitness. -
Moreover, it bears repeating that in July 2013,' in connection with the paternity action which they encouraged Mother to file, Respondents agreed to a consent judgment with Father in which they agreed that Child’s best interests were served by Father having joint legal custody and sole physical custody of Child. Thereafter, Father exercised his parental rights as guardian for Child and provided for Child’s custody and care. The evidence consisting of the consent judgment from the paterni*218ty action was before the court and we find it represents substantial evidence that at a minimum in July 2013, Father was deemed fit enough by the court in the paternity action — and by Respondents who agreed to the consent judgment — to have joint legal and sole physical custody of Child.
Yet, just nine months after the consent judgment was entered, Respondents filed the petition at issue here. While the record here certainly attributes to Father certain deficiencies in comparison to Respondents’ lifestyle, we are not persuaded that there was such a change in circumstances between July 2013 and April 2014 that would justify a complete reversal in terms of an assessment of Father’s fitness. Cf. § 452.410 (“[T]he court shall not modify a prior custody decree unless ... it finds, upon the basis of facts that have arisen since the prior decree or that were unknown to the court at the time of the prior decree, that a change has occurred in the circumstances of the child or his custodian and that the modification is necessary to serve the bests interests of the child.”).
While a change in circumstances in this context is not mentioned by the guardianship statutes, “[t]he rationale for requiring a substantial change in the circumstances of the child or the custodian, whether parent or third party,. includes the desire to maintain a stable nurturing environment for the child,” and further supports that Father should remain as Child’s custodian. See Searcy v. Seedorff, 8 S.W.3d 113, 117 (Mo.banc 1999).
Moreover, the record actually appears to support that the only change from the prior paternity judgment to the time of the filing of the petition here was that Father’s fitness as a parent seemed to have improved. The GAL opined that Father had gotten his act together and that Father is “certainly” not an “unfit parent.” In'addition, the court’s decision to award Father unsupervised visitation also reflects favorably on Father’s fitness and appears at odds with a finding of unfitness.
Conclusion
For the reasons stated above, the trial court’s judgment is reversed and remanded with instructions to dismiss the petition and order that Child be returned to Father’s custody with such custody to proceed pursuant to the terms of ‘ the judgment from the paternity action.
Robert M. Clayton III, P.J. dissents in a separate opinion.’ Lawrence E. Mooney, J., concurs.. All statutory references are to RSMo 2000 unless otherwise indicated.
. We note that Ralls County may not have been the proper venue for this case. Section 475.035 provides that the-venue for the appointment of a guardian or conservator shall be in the county in this state where the minor is domiciled. The domicile of a child is that of the parent who has custody of the child. Beckmann v. Beckmann, 358 Mo. 1029, 2,18 S.W.2d 566, 569 (1949). Here, the petition alleged that Child was domiciled in Ralls • County, Missouri, where Respondents are domiciled. This, however, is not Child’s domicile. By agreement of the parties in the paternity action, physical custody of Child was with Father, who at the time this suit was filed was domiciled in Marion County where the paternity action was venued. Beckmann, 218 S.W.2d at 569. Section 475.040 provides that if it appears to the court that the guardianship proceeding was commenced in the wrong county, the court may on its own motion order that the proceeding be transferred to the probate division of the circuit court- of another county. Because this issue was not raised at trial or- on appeal, we decline to review,the question. ,
. The petition did not allege that Father was unfit but we assume that the parties tried this issue by consent.