Sideways Disinheritance: A Threat to Family Inheritance

Sideways disinheritance is a term that’s increasingly coming under scrutiny in estate planning discussions. It describes a situation in which children or intended heirs are unintentionally disinherited due to the way assets are distributed following remarriage, divorce, or the lack of a robust will. As families become more complex—with blended families, stepchildren, and second marriages becoming more common—the risk of sideways disinheritance has grown. Despite its serious implications, many people are unaware of how it occurs and how to prevent it.

What is Sideways Disinheritance?

Sideways disinheritance occurs when a person’s estate, instead of passing directly to their children or chosen beneficiaries, is diverted sideways—often to a new spouse and subsequently to their children or other relatives—leaving the original heirs with little or nothing. This typically happens when one spouse dies, the surviving spouse remarries, and, upon their death, their estate is passed to the new spouse or their family rather than the children from the first marriage.

For example, if a husband dies and leaves everything to his wife, she may later remarry. Upon her death, her assets—originally including the husband’s estate—could pass to her new spouse or their children, bypassing her original children entirely. This unintended consequence can create conflict and financial hardship, particularly for the deceased’s biological children.

How Does It Happen?

Sideways disinheritance often stems from reliance on standard mirror wills, where each spouse leaves everything to the other. While this seems fair and straightforward, it offers no protection if the surviving spouse changes their will after remarriage. The new spouse may exert influence, or the surviving partner may simply choose to leave everything to their new family. Legally, they are entitled to do so, unless specific provisions are made in the original estate planning.

Another common cause is intestacy—the situation where someone dies without a will. Under the UK intestacy rules, assets go to the spouse and children in a set order. If there’s no will and the surviving spouse remarries, the original intent to pass assets to one’s children may never be realised.

Legal Implications and Family Consequences

Sideways disinheritance is entirely legal, but that doesn’t mean it’s fair or free of consequences. It often results in family disputes, with children feeling excluded or betrayed. Legal challenges to wills—such as claims under the Inheritance (Provision for Family and Dependants) Act 1975—are on the rise, but they can be expensive, lengthy, and emotionally draining. Moreover, these claims are not always successful, especially if the deceased left a valid will and did not owe a financial obligation to the excluded family member.

How to Prevent Sideways Disinheritance

Preventing sideways disinheritance requires proactive estate planning. One effective tool is a family trust. This allows a spouse to benefit from the assets (e.g. live in a house or receive income from investments) for the rest of their life, but ensures that the capital passes to the original children upon their death.

Other solutions include regularly updating your will: Ensure your will reflects changes in your life circumstances, such as remarriage or the birth of grandchildren.

Conclusion

Sideways disinheritance is a real risk that many families face, often without realising it. As family structures evolve, so too must our approach to estate planning. Seeking professional legal advice and creating a carefully considered will are vital steps to ensure that your assets go where you intend. Without such precautions, your children and intended heirs may find themselves disinherited by accident—not by design.