Can an Adult Child Challenge Your Will?

Many parents assume that making a Will means they have the final say over how their estate will be divided. In most cases, their wishes will be followed. However, in NSW, certain people including an adult child may be able to ask the Supreme Court for further provision from an estate under the Succession Act 2006.

That does not mean an adult child is automatically entitled to an equal share, or that leaving a child out of your Will makes the Will invalid.

In short: an adult child can challenge the provision made for them in a Will, but having the right to make a claim is only the starting point. Whether the claim succeeds depends on the circumstances of the family, the estate and the people involved.

What Is a Family Provision Claim?

An adult child who believes they have not been adequately provided for may apply to the Supreme Court of NSW for a family provision order.

Generally, the application must be made within 12 months of the deceased person’s death, although the Court can allow a late application in some circumstances.

The Court can consider a wide range of factors, including:

  • the relationship between the deceased and the child;
  • the size and nature of the estate;
  • the child’s current and future financial resources and needs;
  • the financial circumstances of other beneficiaries;
  • any disability or health issues;
  • whether the deceased had previously provided financial support; and
  • any other circumstances the Court considers relevant.

There is therefore an important distinction between being eligible to make a claim and having a strong claim. The Court does not simply divide an estate equally between adult children because one beneficiary is unhappy with the Will.

Does a Parent Have to Leave Their Children Equal Shares?

No. There is no rule requiring parents to divide their estate equally between their adult children. A recent NSW case illustrates this clearly.

Girotto v Girotto [2025] NSWSC 616

In Girotto v Girotto, a mother left one son a fixed legacy of $300,000, while most of the remainder of her estate went to her other son.

The son receiving $300,000 sought further provision from the estate.

The Supreme Court dismissed his claim, finding that the provision made for him was adequate in the circumstances despite his brother receiving considerably more. The mother’s detailed notes explaining her estate planning decisions were also important in demonstrating her intentions.

The case is a useful reminder that unequal does not necessarily mean legally inadequate.

Where beneficiaries are being treated differently, carefully documenting the circumstances and reasons behind the estate plan can become particularly important if the Will is later challenged.

When Can an Adult Child Succeed?

Another NSW Supreme Court decision from 2025 provides a useful contrast.

Sutcliffe v Harper [2025] NSWSC 54

In Sutcliffe v Harper, an adult son sought further provision from his mother’s estate after receiving a smaller share than his sister. After considering his circumstances, the relationships involved and the position of the competing beneficiary, the Court made further provision in his favour.

The two cases demonstrate why there is no simple formula. An adult child may succeed even where they have already received something under the Will. Equally, receiving substantially less than a sibling does not automatically mean the Court will make further provision.

Can You Prevent Your Will From Being Challenged?

It is generally not possible to guarantee that nobody will challenge an estate. Simply stating in a Will that a person is to receive nothing, or saying that you do not want them to make a claim, does not necessarily remove their legal right to apply for family provision.

However, careful estate planning can help reduce the risk of disputes and place the executor in a stronger position if a claim is made. This may include:

  • reviewing your Will when family or financial circumstances change;
  • considering the needs and circumstances of potential beneficiaries;
  • documenting the reasons for significant or unusual decisions where appropriate; and
  • ensuring your broader estate planning arrangements are consistent with your intentions.

This can be particularly important in blended families, estranged family relationships, substantial estates and situations where adult children have very different financial circumstances.

Can an Adult Child Challenge a Will If They Are Financially Comfortable?

Potentially, yes. Being financially independent does not automatically prevent an adult child from making a claim. However, their income, assets, earning capacity and financial needs are among the matters the Court may consider, together with the size of the estate and the circumstances of other beneficiaries.

That is why family provision claims depend heavily on the individual facts of each estate.

Estate Planning Is About More Than Writing a Will

A carefully drafted Will is an important part of an estate plan, but good estate planning also involves considering where disputes may arise after you die.

If you intend to leave significantly different amounts to your children, exclude an adult child, or have complex family or financial circumstances, obtaining appropriate advice can help ensure your intentions are clearly documented.

Likewise, if a parent has died and you believe inadequate provision has been made for you, strict time limits apply and it is important to obtain advice promptly.

WMD Law’s experienced Estate Law team advises clients on estate planning, Wills and family provision claims. If you are concerned about the risk of your Will being challenged or believe you may have a claim against an estate we can advise you on your options, please click here to contact us or call 9525 8688.

By Greg Dickson, CEO & Accredited Specialist in Family / De Facto Law, WMD Law