The Curious Case of the Marquess of Bath: Surrogate Born Children, Inheritance, and Trusts

The High Court’s ruling in Cator v Thynn (2026 EWHC 209 Ch) highlights an increasingly important question for families who grow through surrogacy: how can parents ensure that their surrogate-born children are fully recognised and protected when it comes to inheritance and family wealth?

The First Surrogate-Born Aristocrat

The eighth Marquess of Bath, Ceawlin Thynn, and his wife, the Marchioness of Bath, Emma Thynn, are no strangers to the public eye, having opened the doors of their stately home for “All Change at Longleat”, as well as featuring in Strictly Come Dancing and Celebrity MasterChef.

After the Marchioness suffered from the hypophysitis during her first pregnancy and was advised that a further pregnancy could be life-threatening, the couple welcomed their second son through surrogacy. Lord Henry Richard Isaac Thynn was born in 2016 in California in the United States. As the first aristocrat born via surrogacy, his circumstances shine a spotlight on the gap between modern family-building and traditional inheritance frameworks.

The Law on Surrogacy and Inheritance

Surrogacy is now a well-established way to grow a family, with around 400 children each year born to UK parents through domestic and international arrangements.

Under the law of England and Wales, the starting point is:

• The surrogate is the child’s legal mother, regardless of biology.
• If married, the surrogate’s spouse is the second legal parent.
• Intended parents have no automatic legal parentage at birth (irrespective of biology and even if their parentage is recognised in other countries).

Intended parents must apply for a parental order (or adoption) to become the child’s legal parents. Transferring legal parentage is an important milestone: it provides parental responsibility and legal recognition.

Importantly, a child born through surrogacy cannot inherit from their intended parents (or grandparents) based on the rules of intestacy or using the definitions of “issue” or “children and grandchildren” as seen in most wills, at least until a parental order or adoption is granted. Intended parents can make a will and specify precisely what references to children mean but will need to address the period between the child being born and a parental order being made.

These laws have been criticised for failing to reflect the reality of many modern families. However, Cator v Thynn demonstrates how trusts can be even further outdated. Trusts are a popular way to protect family wealth, but many long-standing trusts use language that can unintentionally exclude children who were born via surrogacy or other forms of assisted reproduction from benefitting from them. Existing trusts should be reviewed as the language used may not bring a child born through surrogacy into the class of beneficiaries at all.

Litigation at Longleat

Like many others, the Marquess’ wealth is tied up in trusts that rely on pre-1970, common law meanings of family, which can include language like “heirs of the body” and “en ventre sa mere” (in the mother’s womb). As matters stand, the trust excludes Henry from the class of beneficiaries entitled to access various trust funds, simply because he was born via surrogacy and this does not fall within the historic definition of a ‘legitimate child’, despite being genetically the son of the Marquess and Marchioness.

In Cator v Thynn, the Marquess and the trustees asked the High Court to approve their decision to use a power of advancement to allow Henry, and his future descendants, to be added to the class of beneficiaries of his family trusts, worth an estimated £157 million.

At the initial hearing, the Court dealt with a preliminary procedural issue: whether existing beneficiaries (including Henry’s older brother and any future children) should be formally represented in the proceedings. The Court determined they should and appointed an independent solicitor. The next hearing is expected to address the central question: whether the trustees can, and should, exercise their powers to include Henry as a beneficiary.

Whilst this application challenges ancient ideas of inheritance in the Peerage system, it also highlights tensions between modern families and the trusts they use. As the judgment records, the family considered it would be “unfair and unfortunate” if Henry were excluded purely due to the route through which he was born.

The Marquess’ proposed solution in Cator v Thynn may offer useful guidance in the future, if indeed successful. At present, modern families should firstly carefully consider whether the trusts governing their wealth properly reflect their intentions.

International Surrogacy Considerations

A further complication the family faces is Henry’s birth in California. The Marquess has explained that even if his application succeeds, he will not add Henry to the trusts immediately due to potential US tax implications which need to be explored further. This is a reminder that international surrogacy brings additional legal and financial considerations beyond parentage alone.

Considering Surrogacy? Steps to Protect Your Family

Although the Longleat case is rooted in aristocratic wealth, the legal issues are increasingly common. If you are considering surrogacy, or looking to ensure your legal arrangements properly protect your children and future family, you may wish to consider:

• Getting advice on legal parentage, including the parental order process.
• Reviewing trust deeds and wealth-protection structures to ensure children will not be unintentionally excluded.
• Updating your will, especially while awaiting a parental order.
• Reviewing pre- or post-nuptial agreements where family wealth is involved.
• Taking advice on international arrangements, which may have tax or cross-border legal consequences.

Our Family and Private Client Advisory teams have specialist expertise in surrogacy, modern family structures, and wealth protection and can help you plan with confidence.