Mind the child: when is a child not a child in a will or trust?

In this two-part series, the private wealth team looks at how estrangement, blended families, and surrogacy are challenging the meaning of ‘children’ in wills and trusts.

The traditional definition of ‘child’ is being challenged in the courts. It is important to ensure that when individuals refer to their children in a trust or will, the definition of ‘child’ matches those they wish to benefit.

This article considers how the courts are increasingly being asked to scrutinise this definition, and the consequences, including potential claims under the Inheritance (Provision for Family and Dependants) Act 1975 (the 1975 Act). The next article will examine these issues in more detail in the context of blended families and surrogacy.

Traditional definition of a child

The legal definition of ‘child’ has its origins in common law. Historically, a narrow and more formal approach to the meaning of a child was adopted, which focused particularly on the marital status of the child’s parents. Within this framework, children included legitimate biological children (ie children born within a marriage), while for those born outside of marriage, questions of legitimacy could be determined by reference to the law of a parent’s domicile at the time of a child’s birth.

Such common law principles could be displaced by reviewing an individual’s intention at the time a document was prepared and demonstrating their wishes were, for example, that all their children should inherit, whatever their legal status. Establishing such intention, and a child’s right to benefit, could however prove difficult where the instrument was executed many years before a specific beneficiary was born.

Over time, and with increasing societal changes, multiple questions have been raised by families and the court about the definition of a child. Such questions included whether this encompassed legitimated children, or those adopted or born through surrogacy. Legislative reforms have helped to identify and clarify some of these issues. The Legitimacy Act 1976, for example, ensured that children were treated as legitimate from the date of legitimation. The Adoption and Children Act 2002 confirmed adopted children could be treated as legitimate children of their adopters (if married or joint adopters) or adopter (if single) from the date of adoption, and not of other individuals. The Human Rights Act 1998 has also been considered by the courts when determining the definition of a child; for example, in situations where the application of legislation enacted after a will or trust was created would otherwise have resulted in different treatment of children under the instrument.

This statutory framework does not automatically extend to all modern family arrangements. Stepchildren, for example, can be excluded unless adopted or expressly named. The legal status of a child born through surrogacy is also complicated and requires careful consideration.

How the courts are being asked to review the definition of a child

Claims made against an estate under the 1975 Act already recognise a broad category of claimants, including individuals who were treated as a child of the family even if there was no biological or adoptive relationship.

By contrast, when interpreting a class of beneficiaries under a will or trust, the court will look to the instrument itself, and consider the definitions used and the intention behind the drafting of the document.

Blended families carry a higher risk of litigation

In O’Herlihy v Taylor [2026] EWHC, the son of Mr Taylor’s former partner brought an out-of-time claim against Mr Taylor’s estate, for reasonable provision under the 1975 Act, after being excluded from his will.

The claimant, Mr O’Herlihy, had lived with his mother and her partner, Mr Taylor, as a child from 1995 to around 2005, when the relationship ended. Mr Taylor then went on to remarry, although he continued to provide financial support to the claimant until around 2012, pursuant to a separation agreement. As he had issued the claim form more than four years after the expiry of the six-month time limit prescribed by the 1975 Act, Mr O’Herlihy needed the court’s permission to pursue his application.

Ultimately, Mr O’Herlihy’s claim failed. The court ruled he had no real prospect of establishing that Mr Taylor, at his death in 2019, had any obligations or responsibilities to maintain Mr O’Herlihy, particularly as he was earning his own salary which they felt provided sufficient financial support. If Mr Taylor had died at a time when he was providing financial support to Mr O’Herlihy, however, the court may have ruled differently; it noted that Mr O’Herlihy had a real prospect of establishing that the deceased had treated him as a son or stepson between 1995 to 2005.

From a practical point of view, this case highlights how important it is to consider the status of a child within a family throughout the lifetime of an individual. Circumstances and financial obligations do change and documents may need to be amended or drafted to reflect new family structures and dynamics. An individual may need to consider whether they have unintentionally assumed a parental role (regardless of any marriage or civil partnership) within their family. As well as children and those treated as such, any individual who was being financially supported by the deceased prior to death may also have a claim. Financial support can be given informally, for example, through a form of paid or unpaid employment or rent-free accommodation.

Whilst blended families, surrogacy and estrangement may not feel immediately relevant, this case highlights the importance of ensuring that wills can accommodate family changes as they evolve over generations. Potential claimants under the 1975 Act should also be aware of time restraints, which could affect their ability to bring a legitimate claim.

Adult-child claims: increasing, but still highly fact-specific

O’Herlihy v Taylor also shows us how fact-specific these claims can be. The court highlighted that Mr Taylor had ceased to financially support Mr O’Herlihy and communicated that he was no longer responsible for Mr O’Herlihy from 2012. Moreover, the court emphasised that after 2012, Mr O’Herlihy was living his own separate life and supporting himself with no assistance from Mr Taylor.

The facts in this case suggest that whilst Mr O’Herlihy might have been treated as a child of the family, when he was still financially dependent on Mr Taylor, that clearly stopped in 2012.

This can be contrasted with the recent case McDaniel v Talbot [2026] EWHC 928 Ch, where an estranged adult daughter brought a successful claim against her father’s estate. The claimant, Emma McDaniel, had been abandoned by her father when she was eight months old but had, in the years preceding her father’s death, reconciled with him and even provided him with some care. The court balanced the fact that the father’s widow had been sufficiently provided for with Ms McDaniel’s own financial position, care responsibilities and circumstances. The court described Ms McDaniel as a ‘necessitous claimant’. This case highlights the need to keep wills under review as the circumstances here had changed significantly between the father’s 2014 will (which had specifically excluded Ms McDaniel) and his death in 2022. Further detailed commentary on the case is available here.

The private wealth team has already discussed the need for proper planning in its article ‘Next-gen at the helm: managing wealth, relationships and risk‘, but in the context of potential claims, careful attention needs to be given to parental behaviour in supporting not just their children, but children of new partners, partners of such children, or other people treated as a child of the family. We are beginning to see the baby boomer generation reach the age of retirement and pass their wealth to the next generation, otherwise referred to as the ‘Great Wealth Transfer’. This combination of a generation struggling to become financially independent matched against a generation with significantly more wealth creates fertile ground for disputes and to bring claims under the 1975 Act.

For legal practitioners, it is vital to obtain a comprehensive understanding of a client’s circumstances and to remind them when changes to these merit a review of their legal position. Practitioners might want to recommend key life circumstances where the client contacts them for a review (such as marriage, death of a loved one, financial changes or a birth) to ensure any estate planning or documents continue to reflect their wishes.

Wills and trusts need more cautious administration

All these cases show the need for careful attention to the trust or will document during administration and the need for advice before distribution or the exercise of any powers.

In O’Herlihy v Taylor, the claim was brought four years after the six-month limitation period had expired. It is important to remember that a court is afforded discretion to allow a late claim, even if the estate has been distributed. Premature distribution can present a real risk to the executors or trustees where there are potential claims.

The importance of letters of wishes

The letter of wishes is often overlooked or seen as something that can be done later because it does not require the same strict formalities as the will.

This is particularly true for clients who have previously acted in a parental role (as seen in O’Herlihy v Taylor). A contemporaneous explanation is useful not just in future proceedings but also can be used in lifetime to manage the expectations of potential litigants and deter litigation.

Conclusion

What begins to emerge from recent cases is the increasing tension between traditional legal definitions and the realities of modern family life. As surrogacy, estrangement and blended families make up more of our social fabric, a private-client practitioner is not just being asked to prepare an isolated will or trust document. They must understand a client’s holistic family dynamics and ensure these are properly reflected, including any definition of child, in any will or trust they draft. Such steps are vital to reflect an individual’s’ wishes and to reduce the risk of a costly dispute at a later stage.