The death of a close family member one is always a stressful time but things can turn nasty if someone feels they have been unfairly treated in their will.

Increasingly, they are willing to do something about it.

New research shows that a growing number of Brits are now likely to contest a will if they feel it was unfair or has wrongly excluded them.

Six in 10 Britons say that rather than accept the injustice, they will take up cudgels to get what’s due them, according to new research from JMW Solicitors.

Yet few understand what it means to contest a will in practice, or the grounds on which they can be contested.

In practice, anybody who wants to contest a legacy must be prepared for a long and painful struggle.

They also need to be sure they have a strong legal case and legal representation is therefore vital, said Alison Parry, head of will disputes at JMW Solicitors.

“If you believe that you have been deprived of money that is rightfully yours, be prepared to challenge it but accept that this won't be an easy process.”

You may contest a will if you believe the basics have not been done properly, she said. 

“A will must be signed by a testator – the person drawing up their will – in the presence of at least two witnesses, who must also sign there and then. If this wasn’t done correctly, the will can be contested.”

Wills can also be contested if the person giving the instructions lacked mental capacity at the time. “They must understand the nature and effect of making a will and who they ought to be considering for inclusion.”

If they weren’t of sound mind, you have grounds to contest provided you can prove that they did not understand or approve of its contents. 

Parry said that iIf someone is blind, hard of hearing, or does not have English as their first language, they may be unable to review the contents of the will themselves.

Instead, they may place their trust in someone else to do this for them. “When this happens, there is a risk the will will may not reflect the deceased’s wishes,” she said.

If there is evidence to suggest that someone has tried to influence the contents or provisions of the will, it may also be possible to mount a challenge.

Poisoning of the mind is another reason to protest, say, where someone makes false statements about a potential beneficiary whose share is subsequently reduced or cut out altogether as a result. "However, as with undue influence this can be difficult to prove,” Parry said. 

Fraud or forgery also offer grounds to contest but again, strong evidence is required.

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You may even be able to make a claim for “reasonable provision” from someone’s estate, even where there are no grounds to contest the will or the person died without writing one at all.

Parry said a spouse or civil partner (or former spouse or civil partner) might be able to bring a claim for reasonable provision, as might a cohabitee.

A child of the deceased, or a child who was being maintained by them, may also claim. "The category into which you fall will affect how much you could expect to get.”

The time limit for contesting a will varies depending on what grounds you are using to try to contest the will, but ranges from six months to none at all.

To stop the probate process and contest a will you will often have to enter a caveat, Parry added. "A caveat essentially pauses the whole process for six months, though this can be extended."

Parry warned that contesting a will can be a stressful process. "It is key that you understand the implications and consider speaking to a solicitor at an early stage.”

Like all family arguments, things could turn nasty and leave lifelong scars. Even Meghan now wants to end her family feud. So decide whether the pain is worth it.