Bruce Willis’s eldest daughter has spoken about her “terrifying” but powerful choice to take a genetic test to find out her risk of developing Alzheimer’s disease.

In a social media post this week, Rumer Willis said she missed “a different version” of her dad, who made his name in films such as Die Hard and The Sixth Sense before being diagnosed with  frontotemporal dementia in 2023.

“There are some days that are just so hard,” she said in an Instagram video where she shared both old and recent photos of herself with the Hollywood star.

“I try to prioritise being present with where he is at now. The truth is, to be strong is learning to deal with both things at the same time.”

The 38-year-old – who is the eldest of three daughters Willis shares with his ex-wife, fellow actor Demi Moore – revealed earlier this year that her father, now 71, had gone from being a “kind of macho dude” to a much gentler and more tender man.

In her latest update, she shared that she had done a genetic test called the ApoE test to try to find out her own risk of developing Alzheimer’s.

“Which obviously is kind of important – I wanted to check [it] out because of my family history,” she said.

“I have a three-four, which is pretty average, but it also just means that there is some risk, but it’s not crazy.”

Rumer Willis did the test through her partnership with a company called Function, which offers more than 160 lab tests covering everything from food allergies to brain health and cancer detection.

“It’s terrifying to get answers sometimes,” she told People magazine, adding that there were other genetic conditions in her family, including breast cancer.

“But I think when you have information, it’s power.

“And that sounds so, like, Spider-Man, but when we’re able to see, OK, maybe I’m more predisposed to this, you can just start actively working to reduce inflammation in your body, work on heart health, whatever it is.”

 

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Rumer Willis’s comments accord with the advice of Function, which suggests its test results can guide targeted diet and lifestyle changes.

The company’s website explains that the ApoE test looks at genetic variations in the gene apolipoprotein E, adding that “specific ApoE gene variations are associated with an increased risk of cardiovascular disease and late-onset Alzheimer’s”.

According to Dementia Australia, however, having a risk-factor gene for Alzheimer’s disease “only makes you slightly more likely to develop it than someone who doesn’t”.

There are three variants of apolipoprotein E (ApoE): type 2, type 3 and type 4. Every person has two types (sometimes two the same), with type 2 appearing to reduce the risk of developing Alzheimer’s, while type 3 (the most common) doesn’t seem to affect the risk.

People with at least one type 4 are considered at higher risk of developing the disease than those with other types.

“But the risk isn’t that much higher: Half of all people aged 85 who have two copies of type 4 don’t have symptoms of Alzheimer’s disease,” says Dementia Australia.

The Mayo Clinic reports that many people who don’t have an ApoE type-4 variant also get the disease, with things such as lifestyle also considered potential contributing risk factors.

Australian actor Chris Hemsworth’s revelation several years ago that he carries two copies of the ApoE4 gene variant sparked a lot of discussion about Alzheimer’s risk, as did the subsequent release of a documentary in which the Thor star embarked on a poignant road trip with his father, Craig, who was diagnosed with the disease.

@pagesixChris Hemsworth opened up to Theo Von about inheriting two copies of the APOE4 gene 💔 🎥: This Past Weekend/YouTube♬ original sound – Page Six

“This has become a very prominent conversation in my world, because I also have two copies of the gene that puts me in a higher-risk category for Alzheimer’s,” Chris Hemsworth said in the documentary, A Road Trip to Remember.

“But it’s not a problem at this point, and it may never be. So I’m far more focused on my dad right now.”

A Dementia Australia article published around the time Hemsworth first spoke about his Alzheimer’s risk said that genetic testing was not routinely offered for families in Australia, adding that the decision was a “very complex” one in which both the advantages and disadvantages should be considered.

Alzheimer’s is also a different form of dementia to frontotemporal dementia (FTD), which Bruce Willis was diagnosed with three years ago. FTD can cause changes in behaviour, personality, language and movement.

Willis’s wife, model Emma Heming Willis, with whom he has two children, has spoken previously about the “subtle symptoms” she first noticed in the actor and released a book in 2025 about their journey.

She also revealed earlier this year that her husband has never been aware he has dementia.