Mum's pain as son, 8, with 'childhood Alzheimer's' no longer recognises her

A mum has to face the heartbreaking experience of her son, 8, not recognising her when she picks him up at the school gates, due to him having 'childhood Alzheimer's'.

Stanley Barnes was diagnosed with Sanfilippo, a condition for which there is not yet a cure, and is likened to Alzheimer's. Symptoms mean the young schoolboy can't communicate with his parents anymore, or remember words like 'apple'.

Despite him mostly remaining physically active, mum Mari Barnes, from Cornwall, says that devastatingly, her son doesn't know who she is when she goes to pick him up from school.

Stanley was first diagnosed with the condition at just 16 months old, but has now begun to deteriorate rapidly, with Mari saying she feels like she is "losing a part of him everyday."

Watch: Toddler with no legs defies rare condition by showcasing handstands and flips

But, despite the difficulty she and her husband Ross have experienced, Mari has spoken out to raise awareness of the rare condition and pay tribute to Stanley's bravery.

Mari says, "He's quite dramatically gone downhill this year – he's lost all his words.

"It's really hard, it feels like you're losing part of him each day. This is rapid, just six months ago he might have been able to acknowledge you or say something.

"It's a bit like childhood Alzheimer's – that's the easiest way to describe it to someone. He's just basically losing skills."

Explaining how the family now appreciate the little things, she says, "Over the weekend he [Stanley] had a burger, and managed to say the word burger, and honestly I nearly cried. We haven't had that recognition or anything for quite some time.

"It makes it all the more special to know that he is still in there."

The life expectancy of Sanfilippo is between 10-20-years-old.

When Stanley was two, he underwent a two year trial at Great Ormond Street Hospital. Mari explains, "It was really quite invasive, they put a gate inside his body that went into his spinal column.

"They then injected that port with the enzyme that he was missing every two weeks, so that was quite full on.

"We were on that trial for two years which kind of gave us a bit of hope that it would slow down the progression of his disease a bit and give him a better quality of life for longer.

"To an extent I think it has helped Stan, he's eight now and compared to a lot of others with his condition he's in relatively good nick.

"We are just trying to give him as many joyful experiences as possible. I'm no longer trying to teach him new skills but we are trying to maintain ones he has already learned."

Impressively, Mari says this included a challenge of walking 10 miles in a week for Children in Need last year, appearing on the live show after raising nearly £5k.

Read more: Charlotte Church opens up about her dad’s rare illness

She continues, "His first year was relatively normal. Then I saw a big change in him. He stopped hitting those milestones, and we got referred to a paediatrician – so we got a really early diagnosis.

"A lot of children don't get diagnosed until school age, people tend to just think the child might be autistic, but then it's bizarre, because they'll have the word for 'apple' one day and then not have that word the next day. Or they might have forgotten how to do a task like pick up a pen, things like that – so those are the alarm bells.

"There is a look as well. (Children with the condition) have shorter limbs, and larger eyebrows, and a blackened nose bridge – it looks quite sweet in a way – but it can get stronger as they get older. It's just a result of the disease."

Mari explains that as Stanley's cells are lacking in enzymes that clean out toxins, as he gets older those toxins build up, resulting in everything starting to shut down.

Read more: Woman lost twin babies - but gave birth to two more

She adds, "He's physically able still, but he's stiffening up and isn't covering as much distance as he once did – but we've got the liveliest dog on the planet to help keep him going walking every day."

Stanley is still in mainstream school, which Mari says is "amazing".

But, she adds, "Unfortunately with teaching him language, he has lost that skill now. There's nothing more we can really do, so there's daily 'bad news' phone calls from professionals.

"We know he's losing skills, but then the fact he cans till walk ten miles and raise five grand for charity shows he still has such an effect on people. He's so positive.

"He's lost his cognitive ability at the same time as losing his speech, so although that is quite hard he doesn't get frustrated. He's just sort of happy as he is, he's functioning like an eight-month-old baby now."

Mari says, "He's a big boy, he's strong" and and that he's still "really quick and really agile."

Watch: Six-year-old girl who was told she may never walk again defies all odds

Mari and her husband Ross also spent Stanley's early years giving him as many experiences as possible, including a trip to Lapland with the Make a Wish foundation.

Speaking on the initial diagnosis, Mari says, "Having received the news when he was only sixteen months old, that was the point when it was hardest and when I Googled everything I could possibly learn about the disease.

"It was horrific, just awful, but at the same time it wasn't this little boy that we had in front of us. It certainly wasn't our story yet." Now, she says, "The minute I leave the house I have to hold his hand, otherwise he just goes off in a different direction."

Read more: World's most expensive drug gives terminally ill baby future back

She adds, "Like with Alzheimer's, he has some early memories he recognises. If we walk past the nursery for example, he sometimes tries to go in, and he remembers songs we used to sing him because his face lights up.

"He loved Frozen for example, so if that ever comes on the TV he gets so excited and might jump and yell around the TV.

"I don't know how much longer that will last though."

Mari said she wants to raise awareness of Stanley's condition to help others going through a similar experience.

For support with the Sanfilippo, also called MPS III, or to find out more about it, you can contact the MPS Society on 0345 389 9901 or 07712 653 258 or visit the charity's website.