'What's wrong with Dad?' was the heartbreaking question Natasha Young, 50, had been hoping one of her children would never ask. 

But after months of slowly watching her husband, then 51, slowly lose his spark, it was only a matter of time before her then 21-year-old son began noticing it too.

By late 2019, even Natasha's young daughters, Amelia, seven, and 10-year-old Isla, were curious why their fun-loving father no longer seemed interested in family bike rides on the weekend.

In the week, 51-year-old Gary, then working as a self-employed joiner, was coming home reporting that he 'didn't feel right' and that simple tasks were suddenly challenging. 

Doctors were certain at the time that Gary's shift in mood was a clear sign of depression and prescribed him a course of anti-depressants to help improve his mood. 

But instinctively, Natasha, knew 'it was more than that', and after four months of repeated calls to the doctors during the Coronavirus lockdown, a face-to-face appointment was finally booked for Gary at a memory clinic. 

A comprehensive test and subsequent MRI would reveal the striking extent of Gary's cognitive decline. Gary, who at that stage was aware that this was becoming something serious, was becoming increasingly more 'anxious' without an answer. 

Standing in their kitchen at their home in Berwick Upon Tweed in 2022, the pair received a phone call with the news they were never expecting. Aged 51, Gary had Alzheimer's disease.

'Never in a million years did I ever think he would have dementia or Alzheimer's because at that age you just wouldn't think about anything like that and I've never heard of anybody young getting it,' Natasha said.

'In my naive little world I thought it was impossible to get at that age. Gary's always had a six-pack, he's never taken drugs, never smoked in his life, hardly ever drank.

'It was a relief in some ways that we knew we hadn't been completely losing it but at the same time our entire lives just stopped.'

When Natasha and Gary were first introduced via a mutual friend 27 years ago, they were surprised that their paths had not crossed sooner. 

The pair grew up on the same street and even went to the same primary school, and it wasn't long before they became inseparable.

At the time, Natasha already had a six-year-old daughter Amber, from a previous relationship and just two years later they welcomed Nathan, now aged 25, followed by their two daughters Isla, born in 2011, and Amelia, in July 2014. 

'Gary and I have thankfully always had a really close and tight relationship. Of course we've had our bickering moments, but our relationship has been solid. We did everything together,' said Natasha. 

For several years, they were the picture-perfect family. Natasha re-trained as a teacher, while Gary's self-started joiner business was making great strides. 

But towards the end of 2019, Natasha began to notice that her husband appeared different. 

She recalled: 'He kept coming home and just saying "I don't know what's wrong with me today. I struggled to measure something or I went to the wrong job."

'He was getting things mixed up, he was a little distant, a bit quiet and a bit down.  

'I started thinking that perhaps he had a brain tumour or something has happened to his brain, but never in a million years did I ever think about Alzheimer's.'

However, when they finally found the courage to go to the doctors and explain Gary's symptoms, they were battling with the delays caused by the coronavirus pandemic, and a lack of in-person appointments. 

When the diagnosis of Alzheimer's was finally given, Natasha recalled the instant 'relief' mixed with grave anxiety of not knowing what this could possibly mean for their future.

'I spoke to the children separately about it and while there were tears, they were so young at the time that they probably didn't fully understand it because to them dementia was something that just old people got. 

'I remember Isla asked if he will forget us and obviously I was saying no he'll never forget you, but that wasn't strictly true.'

Shortly after the diagnosis, the family made the quick decision to fly to New York City - the same place Gary and Natasha had spent their honeymoon in 2007, as a final family getaway to ensure that their children would 'never look back with regrets'. 

Now, Gary requires 24-hour care and cannot remember his children's names. While Natasha relies on a carer in the daytime, her evenings and weekends are entirely dedicated towards looking after her husband and ensuring his needs are met. 

But while Natasha is mourning the loss of her and Gary's future, her greatest concern is for the welfare of her two children - whom she believes have been 'really affected' by the diagnosis. 

'On the surface, they're fine. But I can tell it's really affected them,' said Natasha.

'Gary was quite a hands-on dad, he would play football with the girls or take them out for walks and climb into bed to read them a story. But over the past few years, he's become obviously a lot more distant from all that. 

'He wouldn't be capable of doing any of it now. Amelia, the youngest one, is quite angry at the world and will often say "why my dad" or 'why did I have to lose my dad when I was so little?"

'He often just sits staring into space which they find quite frustrating, but we try our best. Isla does a lot of competitive gymnastics which gives her a focus in life. I feel like that has helped a lot.'

While their lives have changed drastically, Natasha and her family are now committed to building the greatest 'catalogue of memories' for their children as possible and taking the positives out of an otherwise heartbreaking situation.

In January, Natasha made the decision to set up a TikTok channel to aid this endeavour, with little idea how much her family's story would touch the lives of many. 

Over just six months, the channel, @dementiadiaries51, has amassed more than 74,000 followers and a remarkable 1million likes - with viewers delighting in following Gary's journey and the highs and lows since his diagnosis.

'We set up the TikTok at the beginning of the year as Gary had been quite down with the weather and we had this idea that we would try and make these daft little clips two or three times a week,' Natasha said.

'Within a week, there was quite a lot of people private messaging us saying that we're helping them because they are maybe at the start of their journey, and it sort of grew from there. 

'When Gary was diagnosed I was so lost and completely alone. I've got some lovely friends, but nobody understands what I'm going through. '

She added that the TikTok videos have not only boosted the spirits of viewers, but also Gary's - who often receives sweet gifts in the post from avid viewers. 

'He absolutely loves it!,' she said. 'Most mornings when we're having our coffees I'll go through the comments and read them to him, and sometimes he'll sit and say "I'm a superstar" or "I'm amazing".' 

As she and Gary continue sharing their lives online, Natasha is hopeful that their story will provide hope to others who also find themselves faced with a midlife Alzheimer's diagnosis.

'The main message I would give to anyone in a similar situation would be that life doesn't need to end when you get a diagnosis. 

'I was totally part of the misconception that Alzheimer's doesn't happen to younger people, but if your gut instinct tells you that something's not right, trust it. I became like a dog with a bone trying to get answers. 

'Nobody thinks it is going touch their family, but It could affect any of us, and it's happening to people even younger than Gary as well. 

'Don't ever think that it couldn't happen to you, because unfortunately it could.' 

Join Alzheimer’s Society’s Forget Me Not Appeal this June. Donate and receive your Forget Me Not badge at alzheimers.org.uk/forgetmenotstories