What are the dangers of mutual wills with regards to stepchildren?

Fri 4 November 2022 What are the dangers of mutual wills with regards to stepchildren?

Many families include children from previous marriages. Testators from such families often want to ensure that both their children and stepchildren are treated fairly, no matter what happens. The problem is that English law has no concept of a joint will: instead, a Will is only ever made by one individual who can (usually) change it whenever they like.

Mutual Wills are a partial exception to this: they are an agreement between two people that they will not change their Wills without consent from the other. This sounds good on paper, but in practice the law on mutual Wills is fraught with difficulty, especially when the Wills do not explicitly state that they are mutual.

Given the complexity of the law on mutual Wills, testators will often make regular non-mutual Wills and will simply trust that their partner will not change their will to benefit only their own children.

Eddie Bell, Solicitor in our Wills, Trust, and Probate team examines a recent case which features arguments about mutual Wills in which the firm’s Contentious Probate department acted.

What was the background?

This case revolves around Wills made in 2017 by Reginald and Maureen McLean. Their son was the defendant. We acted for the ultimately unsuccessful claimants, who were Ian, Sean, and Lorraine. They were Reginald’s children from a previous marriage. The defendant represented himself at trial. The sides of the family did not get on with each other.

Although the focus on this case was on the 2017 Wills, the history goes back to when Reginald and Maureen made their Wills in 2013. These appointed each other, the defendant and Sean as executors. The 2013 Wills divided the estate equally between the claimants and defendant. They benefited the defendant by providing him with a life interest which Reginald and Maureen did not understand and therefore they wanted to review their Wills.

In 2017, Reginald and Maureen instructed solicitors to update their Wills. The solicitor explained that the current Wills were unworkable because executors have to get on with each other and agree.

At the meeting, Reginald and Maureen gave instructions that they wanted to leave their entire estates to each other on first death, and the equally between the four children on the second death. This is a very common and straightforward structure, but it is not always appropriate especially in more complex families.

The solicitor recognised this, and pointed out that if Reginald died first, it was entirely possible that Maureen could then make a new Will that left everything to her biological son (i.e. the defendant) with nothing for her stepchildren. Reginald, however, said that they had been married for 45 years and there was no way Maureen would do that and that he trusted her.

Maureen was present at the meeting and agreed that she would not change her Will to disinherit the stepchildren.

A few months after Reginald’s death, Maureen changed her Will to disinherit the stepchildren and left everything to her biological son.

Maureen died two weeks later. It transpired that she had instructed another firm on the new Will and did not tell them about the ones made in 2013 or 2017.

One other issue was that in around April 2018, Reginald and Maureen sent a letter to the parties in which they discussed their succession plans. They explained that “with our health as it is now, we wouldn’t feel confident to change anything.”

What were the issues?

The claimants argued that the 2017 Wills could not be revoked as they were mutual Wills. The law on mutual Wills is extremely complex, but they are essentially an agreement between two people that they will not change their Will in future without the other person’s consent. The claimants’ position was that the new Will was not effective in leaving Maureen’s entire estate to the defendant. This stemmed from Maureen’s oral representation at the meeting with the solicitor in 2017 that she would not change her Will to disinherit her stepchildren.

The defendant denied that they were mutual Wills. He also counterclaimed that Reginald’s 2017 Will was invalid because he lacked the mental capacity, and that Maureen’s 2017 Will was invalid because his and the claimants’ cousin had unduly influenced her into making it.

The claimants’ position was that the joint letter was further evidence that Reginald and Maureen had agreed with each other not to change their Wills in future, and therefore that they were mutual Wills. The defendant denied this and claimed that the letter was a forgery.

One point raised was whether the concept of proprietary estoppel was relevant in deciding whether the Wills were mutual. Proprietary estoppel requires an assurance made by person A to person B and reliance on that assurance by person B to their detriment. Here, that would mean that Maureen could have made a promise that she would not update her Will and Reginald had relied on it by making his Will in the way that he did in 2017. The detriment would be that he chose to make the Will in that way rather than as he would have “really” wanted.

The defendant also argued that even if Reginald and Maureen had made an agreement to make mutual Wills, this would not be a valid contract for the sale of land. Under the Law of Property (Miscellaneous Provisions) Act 1989, a legally binding contract for transferring land must be in writing. Since their agreement was only oral and the estate included a house, he contended that even if the Wills were mutual, the mutuality agreement would not extend to the house. The claimants argued that this did not apply as the Wills did not mention the house specifically; it was only included in the residue of the estate.

What did the court decide?

The County Court held that both of the 2017 Wills were valid but that they were not mutual Wills.

Previous case law indicates that where people agree to make mutual Wills, a moral obligation alone is not enough. There has to be a legally binding agreement akin to a contract, but it does not have to be in writing. Proprietary estoppel could potentially be relevant, but it was not sufficient on its own to establish mutuality.

Case law also holds that the defendant’s point about a written contract for land does not apply where the land is included in the residue rather than mentioned on its own. In theory, then, where a property is included in residue and there is an oral agreement to make mutual Wills, the property can be caught by the mutuality.

The solicitor’s attendance note from 2017 was very detailed but did not make any mention of mutual Wills. The judge found this surprising, particularly as the revocability of these Wills was brought up in discussion. What it showed, however, is that the idea of making a mutual Will was not discussed and the Court held that the solicitor did not think that he was making one. The Court said that this was fatal to the claimants’ argument.

In addition, Reginald’s statement that he trusted Maureen not to update her Will in future did not show that they were mutual Wills; in fact, they showed the exact opposite. He specifically said that he trusted Maureen implicitly on the basis that they had been married for 45 years, so he did not think that there was any need to enter into a mutuality agreement.

The court held that the joint letter was genuine. When, however, it said “with our health as it is, we wouldn’t feel confident to change anything”, this was not a statement that Reginald and Maureen had made an agreement not to change their Wills. It simply recorded their intention at time of the letter – that they did not want to make any changes at that point. Obviously, this did not in itself indicate whether this was a statement about their wills being mutual or mirror wills because mutual wills can be changed by agreement but the court held that the wills were mirror wills and Maureen’s estate was not bound by her promise to Reginald.

The claimants  have lodged an appeal against the decision of the Court. To be continued...

How could this have been avoided?

As mentioned earlier, it is not always a good idea just to have a simple Will leaving everything to the surviving spouse failing which to children. This is particularly important where there are children from previous marriages and the aim is to treat all the children equally.

One option could have been to make it explicit that the 2017 Wills were intended to be mutual Wills. This would have ensured that Maureen would not have been able to disinherit her stepchildren, but it may have been overly restrictive if there were other changes that she may have wanted to make, such as including legacies to charity or if she required funds from the house for housing care. The law on mutual Wills is extremely complicated, a mutual Will attracts more costs than a normal Will and many couples/partnerships will rely on the trust of another but that trust in itself will not afford any protection as this case proves that a separate agreement would be required.

Many people will not want to pay for mutual Wills as they need to be advised together and individually in relation to the contract between the parties and what would happen if there were a breach. This deals with the specialisms of two separate and distinct areas: private client and contract litigation. The costs could run into thousands of pounds as opposed to a few hundred when dealing with ordinary mirror Wills (i.e. those that do the same things as each other but are not binding). If you want to bind a spouse/partner etc. you must therefore consider paying thousands of pounds for a mutual Will up front or run the risk that intended beneficiaries loose out or face a legal battle to try to recover their intended entitlement with no guarantees of success. 

It may be prudent to instruct solicitors to prepare mutual Wills and pay the costs upfront as opposed to your estate funding the expense of litigation which can run into hundreds of thousands.

A much more practical alternative could have been for Reginald and Maureen to include life interest trusts in their Wills instead of giving everything to the surviving spouse outright. A life interest trust works by giving a person (known as the life tenant) the right to the income from the estate and the right to live in the property, but not access to the underlying capital. On the death of the life tenant, the capital goes to the ultimate beneficiaries, in this case the children and stepchildren. This is the case even if the life tenant has subsequently changed their own Will. It is a shame that the solicitor dealing with the Will instructions did not acknowledge the mutuality nature of the instructions or advise that trust alone is not enough to bind a person’s estate despite promises to the contrary.

It is also a shame that they did not look at the severance of joint property at the Will instruction meeting as this could have allowed 50% of the joint property to go to the stepchildren as Reginald had always intended that all of his children should benefit equally. 

This case, then, serves as a cautionary tale. Relationships in a blended family may be (or at least appear) cordial while everyone is still alive, and so people may trust each other, but this can break down very quickly when the balance of power shifts after a death. Relying on trust alone can be dangerous where hundreds of thousands of pounds are at stake. 

How can Taylor Rose MW help?

At Taylor Rose MW we have a thriving department that specialises in wills and estates. Our team of experts recognise the issues that can arise in blended families where the aim is to treat everyone equally and we can advise you on the various ways to achieve this. To find out how we can help you, call us today on 020 3540 4444 or email us at

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