Best Interests of the Child in Missouri Custody Cases

What "Best Interests" Means in Practice

Missouri law requires every custody decision to serve the child's best interests. That's the legal standard — but it isn't a feeling or a hunch. Under RSMo § 452.375.2, judges must evaluate nine specific statutory factors and weigh the evidence on each one. Understanding these factors is the difference between walking into court with vague assertions about being a good parent and presenting organized evidence that speaks directly to what the judge is required to consider.

The Nine Factors

1. Each Parent's Wishes and Proposed Plans

The court considers what each parent is asking for and evaluates the parenting plans they submit on Form CAFC501. A detailed, co-parenting-oriented plan — one that demonstrates willingness to include the other parent — carries more weight than a plan focused on restricting the other parent's access.

2. The Child's Need for a Relationship With Both Parents

This factor evaluates each parent's willingness and ability to actively perform parenting functions — not just be present, but handle homework, medical appointments, school events, and daily routines. A parent who has historically been the primary caregiver has an advantage here, but the factor also asks whether each parent encourages the child's relationship with the other parent.

3. Key Interrelationships

The court looks at the child's relationships beyond the two parents — siblings, step-parents, extended family, and anyone else who significantly affects the child's well-being. Keeping siblings together is strongly favored unless there's a compelling reason to separate them.

4. Which Parent Facilitates Contact

This is consistently one of the most influential factors. The court evaluates which parent is more likely to allow the child frequent, continuing, and meaningful contact with the other parent. Active gatekeeping — refusing parenting time, blocking phone calls, intercepting mail, or making negative comments about the other parent in front of the child — can shift a custody decision against the parent doing it.

If you're documenting a pattern of gatekeeping, specific records matter: text messages showing denied visitation, emails where one parent refused to share school information, or a log of calls the other parent blocked.

5. Stability and Community

The child's adjustment to their current home, school, and community weighs heavily. Courts are reluctant to uproot a child from a school where they're thriving, a neighborhood where they have friends, or a routine that provides stability. A parent proposing a move to a new city during the custody dispute bears the burden of explaining why the disruption serves the child's interests.

Missouri law explicitly states that courts cannot penalize a parent based solely on the parent's choice to homeschool or enroll the child in a family-paced education program.

6. Mental and Physical Health

The court evaluates the mental and physical health of everyone involved — both parents, the child, and anyone living in the household. This factor includes any history of abuse. An untreated substance abuse problem or a severe mental health condition that impairs parenting ability can tip a custody decision, but the emphasis is on "untreated." A parent who is managing a condition through treatment and medication is in a very different position than one who refuses to address it.

7. Stability and Continuity of Care

Separate from Factor 5 (which focuses on the child's external environment), this factor evaluates the consistency of the caregiving relationship itself. Has one parent been the primary caretaker for years while the other worked long hours? Has the child always gone to one parent when sick or upset? Courts value continuity in these patterns.

8. Intended Relocation

If either parent plans to move the child's principal residence, the court considers whether the relocation is a good-faith career move or an attempt to disrupt the co-parenting relationship. Absent exigent circumstances as determined by a court with jurisdiction, Missouri's relocation statute (RSMo § 452.377) imposes strict notice requirements — at least 60 days' advance notice by certified mail — and the relocating parent bears the burden of proving the move is in the child's best interests.

9. The Child's Own Input

Missouri has no statutory age at which a child gets to "choose" which parent to live with. Instead, the court considers the child's input as one of nine factors, weighted by the child's age and maturity. A judge may conduct an in-chambers interview to hear the child's preferences without subjecting them to open-court testimony or parental pressure.

Case law suggests judges begin giving meaningful weight to a child's expressed preferences around age eleven or twelve, but even then, the child's input is not dispositive — a teenager who wants to live with the permissive parent doesn't automatically get that wish.

How to Prepare

For each factor, ask yourself: what specific evidence do I have? Factor four requires communication records. Factor five requires school enrollment history. Factor six may require medical records or treatment documentation. Generalizations and character testimony matter far less than documented, specific facts tied to the factors the judge is required to evaluate.

The Missouri Child Custody & Parenting Plan Guide includes an evidence-organization worksheet mapped to all nine factors, helping you collect and present the documentation that Missouri judges actually use to decide custody.

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