A MUM has bravely spoken about her son’s life-limiting condition.

Jessica Barcynski, of Farsley, completed the London Marathon to raise awareness and funds for a charity supporting families, after Felix was diagnosed with Leigh syndrome at just six months old.

She ran the 26.2‑mile race on Sunday in aid of the Lily Foundation.

Leigh syndrome is a severe neurological disorder caused by mitochondrial disease – a genetic condition that affects the body’s ability to produce energy.

It is rare, complex, and currently has no cure.

Jessika Barcynski during the London Marathon, which she ran to raise awareness of Leigh syndrome and funds for the Lily Foundation. (Image: Jessika Barcynski)

Mum speaks about son’s life-limiting condition

Ms Barcynski said Felix appeared to be a healthy baby until subtle changes began to emerge.

She said: “He was happy and developing normally, and then he gradually stopped meeting milestones…he became less responsive, stopped smiling, and eventually began having seizures.”

Following a series of intensive tests, including brain scans and neurological assessments, Felix was diagnosed after spending a week on a specialist ward.

Ms Barcynski added: “When you’re told your child has a life‑limiting condition with no cure, it changes everything.”

After finishing the marathon, Jessika Barcynski hugs her son Felix. (Image: Jessika Barcynski)

‘It can feel incredibly isolating’

Because mitochondrial diseases are rare, many families have never heard of the condition before diagnosis.

Ms Barcynski said this lack of awareness can be deeply isolating for parents.

She added: “You can have the best support network in the world, but when something is this rare, people just don’t understand, you need to connect with people who’ve lived it.”

Jessika Barcynski, Joe and their son Felix, whose diagnosis inspired the fundraising effort. (Image: Jessika Barcynski)

Support from the Lily Foundation

Doctors introduced the family to the Lily Foundation shortly after Felix’s diagnosis, offering a vital source of information, support and connection with other families facing the same reality.

Founded in 2007, the Lily Foundation supports families affected by mitochondrial disease while also funding medical research into potential treatments.

Ms Barcynski said the charity has been “a lifeline”, providing counselling, advice and opportunities to meet other families.

Jessika Barcynski with Jon Harris from Guiseley, who also ran the London Marathon to support the Lily Foundation. (Image: Jessika Barcynski)

Running to raise awareness

Ms Barcynski said running the London Marathon was a way of raising awareness of a little‑known condition, as well as giving back to the charity that has supported her family.

She said: “The marathon wasn’t about time or achievement, it was about visibility, and about saying that children like Felix exist, and families like ours exist.”

Jessika Barcynski stops to see her partner Joe and son Felix during the race. (Image: Jessika Barcynski)

Thousands raised for rare disease support and research

Ms Barcynski ran as part of “Team Felix” alongside family friend John Harrison, of Guiseley, with the pair fundraising together.

Their total has now surpassed £11,000, with donations still continuing to come in.

All funds raised will go directly to the Lily Foundation, helping to support affected families and fund research into mitochondrial disease.

“This is about giving back,” Ms Barcynski said.

“If fundraising can help another family feel less alone, or contribute to research that might one day change outcomes, then it’s worth every step.”