To protect children from a previous relationship, the most reliable route is a will that does not simply hand everything to a new partner and hope they pass it on. A common approach is a life interest trust, which lets a partner benefit from your assets during their lifetime while your children remain the people who ultimately inherit.
Blended families face a problem the standard "all to my spouse" will does not solve. If everything passes to a new partner outright, that person can later change their own will, remarry, or spend the assets, and nothing compels them to leave anything to your children. This guide explains the risk and the main ways to plan around it. Figures are current as at August 2026 and are subject to change.
How children from a previous relationship get left out
There are two common ways children lose out, and both are avoidable with planning.
No will at all. If you die without a valid will, the intestacy rules decide who inherits. A surviving spouse or civil partner takes your personal possessions, a fixed statutory legacy, and half of anything above it, with the children sharing the other half (gov.uk, intestacy rules, as at August 2026, subject to change). The statutory legacy is £322,000, set at that level from 26 July 2023 (gov.uk, subject to change). An unmarried partner receives nothing under intestacy, and stepchildren you never formally adopted inherit nothing either. For many estates that means the children of a first relationship receive little or none of what a parent assumed they would.
Sideways disinheritance. This is the bigger risk for people who do make a will but leave everything to a new spouse. Once assets pass outright, they belong to that person. If they remarry, their new spouse may take priority. If they make a fresh will, your children can be left out. This unintended drift of an inheritance away from a first family is often called sideways disinheritance, and a plain "mirror will" between a couple does nothing to prevent it.
Ways to protect children from a previous relationship
The right combination depends on your family, your assets and your wishes. The table below sets out the main tools people use, as general information rather than a recommendation.
| Approach | How it works | Often suits |
|---|---|---|
| Direct gift in your will | You leave a fixed share or specific assets to your children outright, separate from anything left to a partner. | Estates where a partner is financially independent |
| Life interest trust | A partner can live in the home or receive income for life, then the capital passes to your children. | A shared home and a wish to provide for both |
| Property protection trust | Your share of a jointly owned home is placed in trust on your death rather than passing to the co-owner outright. | Couples who own a home as tenants in common |
| Discretionary trust | Trustees hold assets for a class of beneficiaries and decide who benefits and when, guided by your letter of wishes. | Vulnerable children, or uncertain future needs |
Trusts are involved documents, and the tax and practical effects differ, so many people set them up with a professionally drafted will rather than a template. You can read more about how trusts sit within a wider plan in our estate planning guide.
Life interest trusts explained
A life interest trust (sometimes an immediate post-death interest, or IPDI) is the tool most often used by couples in second relationships who want to look after each other and their respective children. On the first death, the assets, often a share of the family home, go into a trust rather than to the survivor outright.
The surviving partner becomes the "life tenant". They can usually live in the property or receive the income from the trust for the rest of their life, and in many trusts the home can be sold and replaced. When the life tenant dies, the trust ends and the capital passes to the people you named at the outset, typically your own children. Because your children are fixed as the eventual beneficiaries when you make the will, the survivor cannot redirect that share to someone else.
A life interest trust separates the right to benefit now from the right to inherit later, so a partner is provided for without your children losing their share.
Where the asset is a jointly owned home, a property protection trust works on the same principle for your half share. This depends on owning the property as tenants in common rather than joint tenants, which is a point worth checking early because joint tenancy passes the whole property to the survivor automatically and outside your will.
Practical steps to put protection in place
These are the elements people commonly review together when planning for a blended family. None of them is advice for your situation, and the order can vary.
- Make or update your will. A will is the document that creates any life interest or discretionary trust. Without one, intestacy applies and your intentions carry no weight.
- Check how you own your home. Joint tenants automatically pass the whole property to the survivor. Severing the tenancy to tenants in common lets each share be dealt with under each owner's will.
- Name guardians for minor children. A will can appoint who cares for children under 18, which matters most where the other biological parent is absent.
- Write a letter of wishes. This guides trustees on a discretionary trust and records your reasoning, though it is not legally binding.
- Consider a lasting power of attorney. A lasting power of attorney lets someone you trust act for you if you lose capacity, which a will alone cannot do. Registration with the Office of the Public Guardian costs £92 per LPA (gov.uk, as at August 2026, subject to change).
- Review after life changes. Marriage generally revokes an earlier will in England and Wales, so a will made before a new marriage may no longer stand.
Inheritance tax and trusts for a second family
Protecting children and managing inheritance tax are separate goals, and a plan that suits one does not automatically suit the other. The standard rate is 40%, charged only on the part of an estate above the available tax-free thresholds. Each person has a nil-rate band of £325,000 and a residence nil-rate band of up to £175,000 where a home passes to direct descendants, both frozen until 5 April 2031, the end of the 2030-31 tax year (gov.uk, as at August 2026, subject to change).
A life interest trust for a surviving spouse or civil partner is generally treated for inheritance tax as though the assets belong to that survivor, so the spouse exemption can still apply on the first death, with tax considered when the trust later ends. The residence nil-rate band has its own rules where a home passes into certain trusts, and it tapers away by £1 for every £2 by which an estate exceeds £2,000,000 (gov.uk, residence nil-rate band, as at August 2026, subject to change). Because these interactions depend on your circumstances, this is an area many families discuss with a qualified professional. Our inheritance tax guide covers the thresholds in more depth.
- Intestacy statutory legacy for a surviving spouse where there are children: £322,000, then half the balance (gov.uk). Unmarried partners and unadopted stepchildren inherit nothing.
- Nil-rate band £325,000; residence nil-rate band up to £175,000, frozen until 5 April 2031 (gov.uk).
- Inheritance tax standard rate 40%, or 36% where 10% or more of the net estate passes to charity (gov.uk).
- Lasting power of attorney registration: £92 per LPA (gov.uk).
Scotland and Northern Ireland
This guide describes the law of England and Wales. Scotland differs in an important way for blended families: children have "legal rights" to a fixed share of a parent's moveable estate that generally cannot be defeated by a will, which can give some protection but also limits how freely a parent can plan. Scotland also uses confirmation rather than a grant of probate. Northern Ireland has its own intestacy rules with different figures. Where an estate touches more than one jurisdiction, it can be worth taking advice in each.
Frequently asked questions
Can my new husband or wife leave my children out after I die?
Yes, if you leave everything to them outright. Once assets pass to a spouse absolutely, they own them and can change their own will, remarry or spend the money, with no obligation to your children. A life interest trust or a direct gift to your children in your own will is how many people prevent this, as general planning rather than advice for a specific estate.
What is a life interest trust?
A life interest trust lets one person benefit from an asset, such as living in a home or receiving income, for the rest of their life, after which the asset passes to different beneficiaries you chose in advance. In second relationships it is often used so a surviving partner is provided for while children from an earlier relationship remain the eventual heirs.
What happens to my children if I die without a will?
The intestacy rules apply. A surviving spouse or civil partner receives your personal possessions, the first £322,000, and half of the remainder, with your children sharing the other half (gov.uk, intestacy rules, as at August 2026, subject to change). An unmarried partner and stepchildren you did not adopt receive nothing, which is why a will matters for blended families.
What is sideways disinheritance?
Sideways disinheritance is when an inheritance intended for children drifts to someone else, usually because a parent left everything to a new partner who then leaves it to their own family or a later spouse. It is a common outcome of "mirror wills" in second relationships, and trust based planning is one way people guard against it.
Do I need to change how we own our house?
Possibly. If a home is owned as joint tenants, the whole property passes automatically to the survivor and outside your will, so a trust for your share cannot take effect. Owning as tenants in common lets each person leave their share through their own will, including into a life interest or property protection trust. Whether to change ownership depends on your circumstances.
Does a life interest trust affect inheritance tax?
It can. A life interest trust for a surviving spouse or civil partner is generally treated as part of that survivor's estate for inheritance tax, so the spouse exemption may still apply on the first death, with tax considered when the trust ends (gov.uk, as at August 2026, subject to change). The residence nil-rate band has particular rules for homes passing into trust, so this is often reviewed with a qualified professional.