Our late father left the family home to his new partner rather than to me and my siblings. He wasn't married to her but they lived in the house together. Do we have any grounds to challenge the will and reclaim the family home we grew up in? Jane Denton, of This is Money, replies: A growing number of families are becoming embroiled in inheritance and will disputes. It is important to highlight just how expensive, stressful and time-consuming challenging a will or seeking to disrupt the administration of an estate can be.More than 11,500 applications to halt the administration of estates were filed in 2025, a 12 per cent year-on-year increase, according to data obtained via a Freedom of Information request by TWM Solicitors. The data revealed via the Ministry of Justice showed that applications for probate caveats, which temporarily prevent a grant of probate being issued, rose from 10,313 to 11,589 last year. A probate caveat enables someone to block the administration of an estate for six months while concerns about a will or the handling of an estate are investigated. Incoming disupute: A This is Money reader's late father left the family home to his new partner Higher property prices and more complex family dynamics are increasing the likelihood of disagreements over wills and inheritance matters. Increasingly, people factor expected inheritance windfalls into their long-term financial planning. When the reality falls short of expectations, it can quickly lead to disagreements and legal challenges.A rise in dementia cases is also leading to more claims that wills were not properly drawn up. You and your siblings do not have an automatic right to get your late father's house, even though it was where you grew up. However, you may be able to challenge the will, but your chances of success would depend on a variety of factors. You wouldn't be likely to succeed if the house is simply highly sentimentally valued by you all. If, however, you or your siblings relied on your father financially and perhaps lived in the house, then the chances of success would be better. Interestingly, under new Government proposals, more than 3.5million cohabiting couples could gain automatic inheritance rights if one of them dies without a will.The broad set of rights are intended to be 'distinct and different' from those of married people, to help 'preserve the sanctity of marriage', according to the Government. Claire-Marie Cornford, partner and head of private client dispute resolution at Irwin Mitchell, says: This scenario is increasingly common, as families are more complex than in previous generations, with second marriages, blended families, and non‑traditional family structures increasingly common.In addition, the rising cost of living means younger generations are more likely to rely on inheritance as part of their financial planning and to provide greater financial security.An ageing population, and the increased prevalence of age‑related conditions such as dementia also sometimes lead relatives to question a loved one’s mental capacity at the time a will was made. Claire-Marie Cornford is a partner at Irwin Mitchell Losing a parent is difficult enough without the added shock of discovering that the family home has been left to someone unexpected. For many, a childhood home carries enormous emotional significance, so it’s not uncommon for this situation to prompt a dispute.Whether you can challenge the will depends on the circumstances, but there are several potential legal routes available to consider.One of the most common is a claim under the Inheritance (Provision for Family and Dependants) Act 1975. This legislation allows certain people, including adult children, to bring a claim if they believe the will does not make 'reasonable financial provision' for them. The court will look at several factors, including your financial needs and resources, the size of the estate, the nature of your relationship with your late father, and any obligations he may have had towards you. For example, if an adult child was financially dependent on their parents, and was living in the family home, or has particular health or financial difficulties, that may strengthen the case. By contrast, if the children are financially independent adults, the court will not intervene solely because the house holds sentimental significance.There are also other grounds on which a will may be challenged. If there are concerns that your father lacked mental capacity when the will was made, did not fully understand its contents, or was subjected to undue influence or pressure by another person, the validity of the will could be disputed. In some cases, disputes also arise where there are concerns about fraud, forgery, or whether the will was properly signed and witnessed.Timing is crucial. Claims under the 1975 Act generally need to be brought within six months of the grant of probate, so it is important to seek specialist legal advice as early as possible. Delays can make claims more difficult and may limit the options available.This scenario is a reminder of the importance of open communication when it comes to inheritance and wills, particularly where a childhood or family home forms part of an estate.Stuart Downey, a partner and mediator who leads the will, trust and estate disputes team at TWM Solicitors, says: You and your siblings potentially have a claim, but it depends very heavily on the facts. If your father left the house to a new partner instead you and your siblings, there are two broad routes that might be considered.The first is a claim under the Inheritance (Provision for Family and Dependants) Act 1975 if the will does not make reasonable financial provision for you. The other route in addition to or instead of the first would be challenging the validity of the will. Stuart Downey is a partner at TWM SolicitorsWhether such a claim succeeds will depend on a number of factors, such as: - your financial needs and resources;- the size and nature of the estate;- your relationship with your father;- any obligations he had towards you; and- the needs of the partner or any other beneficiaries.A key point is that adult children do not automatically have a right to inherit. If you and your siblings are financially independent and were not being supported by your father, that can significantly reduce the prospects of a successful claim.A second possibility is to challenge whether the Will itself is valid. Common grounds include:- lack of proper formalities, for example, if the will was not properly signed or witnessed; - lack of mental capacity; lack of knowledge and approval of the contents; - undue influence; - fraud or fraudulent calumny. These claims are fact-sensitive and usually require detailed evidence, such as the solicitor’s will file, medical records, and witness evidence.Before bringing any challenge, it is essential to ask: what happens if the challenge succeeds and is there an earlier will? If there is an earlier will, who inherits under that will? And if there is no earlier will, would the estate pass under intestacy rules and would the partner then bring their own claim against the estate? Even if a claim succeeds, that does not necessarily mean the house itself would be returned to you. The court may decide that the partner should remain housed there, or that the property should be sold and the estate distributed in some other way.Claims under the 1975 Act are subject to a strict time limit — six months from the date of the grant of probate. While the time limit for will validity claims is more flexible, it is still important to take advice promptly as a claim can fail if there has been too much delay.In short, you may have grounds to challenge, but there is no automatic right to recover the home simply because you grew up there. The strength of any claim will depend on the will, the surrounding circumstances, your financial position, and the evidence available.Help with financial advice and planning Financial planning can help you grow your wealth, sort your pension, or make sure your finances are as tax efficient as possible.Key reasons that many seek financial planning involve investing for retirement and inheritance tax planning.Services such as Unbiased can match you with a financial professional according to your needs:> Find a local financial adviser* Products featured are independently selected by This is Money's specialist journalists. 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