What Is Third-Party Custody?


Trust the Carson Law Firm for expert legal guidance on third-party custody matters. Contact us today for a consultation regarding your case.

What Is Third-Party Custody: What You Need to Know

Are you concerned about the well-being of a minor child who is not your own? Third-party custody allows someone other than the child’s parents to obtain legal and physical custody of the child. This could be any of the following:

  • A relative: a grandparent, aunt, uncle, sibling, etc.

  • A non-relative: a friend, neighbor, foster parent, etc.

To get third-party custody of a child, you must file a petition in family court. However, the process can be complex and may be faced with several challenges. That’s because you need clear and convincing evidence to support your claim as to why you should be given custody. For instance, you need to prove that one or both parents are unfit to care for the child. You must also show that you and the child have a significant and ongoing relationship. The courts will require you to show that you can provide for the child’s:

  • Physical needs

  • Emotional needs

  • Educational needs

  • Medical needs

The court may grant you legal custody, physical custody, or both. If granted legal custody, you get the same rights and responsibilities as a parent, meaning you can make decisions about the child’s education, health care, and upbringing. With physical custody, the child lives with you. 

Third-party custody cases are often not easy to handle alone, as you might have to deal with visitation rights for the biological parents, child support obligations, and possible challenges to your custody status.

The guidance and representation of an experienced child custody and divorce lawyer can be invaluable. At The Carson Law Firm Firm, we have years of experience handling all types of custody cases.

Third-Party Custody vs. Guardianship 

Third-party custody and guardianship are two legal options that can allow you to care for and protect a child in need. Here is how they compare:


  • You file a petition in probate court to become the child’s guardian.

  • You have to show that the child’s parent(s) is/are unfit, unwilling, or unable to care for the child.

  • You have to report to probate court every year. You report about the child’s physical, mental, and emotional health.

  • You do not have to terminate the parental rights of the child’s biological parents.

Third-Party Custody

  • You file a motion in family court to obtain sole or joint physical custody of the child.

  • You have to prove, according to Mo. Rev. Stat. § 452.375.5, that:

    • Each parent is unfit, unsuitable, or unable to be custodian, or

    • The welfare of the child requires your custody, and

    • Taking custody of the child is in their best interests

  • You do not have to report to the court regularly about the child’s well-being.

  • You do not have to terminate the parental rights of the child’s biological parents.

Other distinctions to keep in mind include:

  • A guardianship lasts until a parent asks the court to end it. The court decides if the parent is fit and if it is in the child’s best interests.

  • A third-party custody order stays in effect until the family court modifies it.

  • A third-party custody order can be modified if a change in the child’s or custodian’s situation requires a modification.

Common Third-Party Child Custody Arrangements

In third-party custody cases, the court often grants the custodian both legal and physical custody of the child. This means that the child will only live with the third-party custodian, and all their major life decisions will be made by the custodian. However, custody is decided on a case-by-case basis, and the court always looks at what is best for the child.

Depending on the circumstances and the grounds for third-party custody, the court may approve one of the following custody arrangements:

Sole Custody

In sole legal custody arrangements, the third-party custodian can make important decisions about the child’s upbringing. The child’s parent or parents may have some parenting time with the child, but they do not have any say in major matters.

Sole physical custody means that the child lives mainly with the third-party custodian. However, the child’s biological parents may be allowed to participate in the decision-making power.

Joint Custody

Joint custody means that the third-party custodian may share custody rights with the child’s parents. They work together to decide on the best interest of the child in all aspects of their life. Joint custody can also mean the child spends equal or almost equal time with both the custodian and the parents. This creates a balanced and shared experience. The court usually prefers this type of custody when it’s in the child’s best interests. It benefits the child by maintaining their relationship with their parents.

Contact The Carson Law Firm Today

If you are planning on filing a third-party custody motion, you could use the legal help and guidance of an experienced family law attorney. The Carson Law Firm has handled custody cases of all types, so you can rest assured that you are getting the sound advice you need.

Here’s how our family law attorney can help you:

  • We can explain the legal requirements and procedures for obtaining third-party custody. We can help you prepare and file the necessary documents in the appropriate court.
  • We gather and present clear and convincing evidence to support your case.
  • If your custody is contested, our attorneys can represent you and advocate for your interests in:
    • Court hearings
    • Negotiations
    • Mediations
    • Trials
  • If you are the grandparent of the child, we can advise you on the grandparent’s rights in Missouri.
  • We can help you establish and maintain a positive and stable relationship with the child. We address any issues or concerns that may arise during or after the custody process.

Do you have questions about how child custody is determined in Missouri? Talk to a divorce lawyer at The Carson Law Firm. We are a reputable and trusted family law firm serving West and South St. Louis County.

Contact us today, and let us help you with your third-party custody case.

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