Creates provisions relating to modifying child custody and visitation orders

The bill now repeals and re-enacts three statutory sections (452.375, 452.410, 452.423) instead of just one (452.410), expanding from a focused modification/temporary orders bill to a comprehensive custody law rewrite.

Allows third-party custody (to relatives or other suitable persons) when the court finds both parents are unfit, unsuitable, or unable to serve as custodian.

Adds an entirely new section 452.423 governing guardian ad litem appointments in custody cases, requiring mandatory GAL appointment when child abuse or neglect is alleged, specifying GAL duties (interviews, record review, written reports), and requiring training in child development, trauma-informed practices, domestic violence dynamics, coercive control, mental health disorders, and special needs.

Creates a rebuttable presumption that equal or approximately equal parenting time to each parent is in the best interests of the child, rebuttable only by a preponderance of the evidence. The presumption can also be overcome if parents agree on all custody issues or if a pattern of domestic violence is found.

Requires courts to consider custody arrangements in a specific order: joint physical and legal custody first, then joint physical with sole legal, then joint legal with sole physical, then sole custody, then third-party custody. Joint custody cannot be denied solely because one parent opposes it.

Requires courts to make written findings of fact and conclusions of law when rejecting a proposed custodial arrangement or when awarding custody to an abusive parent despite a finding of domestic violence.

Prohibits courts from adopting local rules or forms requiring a standardized or default parenting plan for interim, temporary, or permanent orders.

Requires all custody orders after August 28, 2016 to include specific language explaining how a party may file a family access motion for noncompliance, including that no legal counsel is required.

Expands the emergency temporary order provision in section 452.381 to specifically include emergencies involving a parent's deteriorating mental health, failure to comply with prescribed treatment, professional reports indicating instability, or patterns of emotional volatility or coercive behavior.

Adds statutory definitions for 'custody,' 'joint legal custody,' 'joint physical custody,' and 'third-party custody' in section 452.375.

Renumbers the best-interests factors from 8 to 9, adding a new factor (7) about the child's need for stability, continuity of care, and consistent routine, and renumbering the child's input factor from (8) to (9).

Prohibits courts from awarding custody or unsupervised visitation to a parent (or person residing with that parent) convicted of listed felonies against children, including sexual offenses, child abuse, and related crimes under chapters 566 and 568.

Grants both parents access to medical, dental, and school records of the minor child unless custody or visitation rights have been denied. Institutions that deny access without good cause face court-ordered compliance plus costs and attorney's fees.

Adds subsection 4 to section 452.410 clarifying that for children with special needs or disabilities, a change of circumstances may include one parent's neglect or harm of the child's best interests.

Adds penalties for parents who refuse to exchange information about the child's health, education, and welfare - the court must order immediate compliance plus payment of the other party's costs including attorney's fees.