Teenager Becky Winstanley has suffered with health problems for most of her life.
But it was only two years ago, at the age of 13, that she was finally diagnosed with cystic fibrosis (CF).
It is an inherited disease caused by a faulty gene, which causes the lungs and digestive system to become clogged with mucus, making it hard to breathe and digest food.
More than 2.5 million people in the UK carry the faulty gene - around one in 25 of the population - and there is currently no cure.
Becky’s mum, Karen, 38, said: “She has always been poorly from about the age of three, always with chest infections and very small for her age.
“It wasn’t until she was 13 that her health deteriorated and I wanted some answers.
“They tested her for a few things and couldn’t figure out what was wrong with her. She was sent to a consultant and tested for CF and it came back positive.
“I was really shocked. I couldn’t understand how she had survived so long without this diagnosis.”
Karen described Becky as being “just skin and bone” when she became ill at the age of 13.
She said: “She did look very poorly. I really thought I was losing her because she was poorly. She wasn’t developing or growing.
“She was still in age eight to nine clothes at 13.
“She couldn’t walk down the street without collapsing because she was in a lot of pain and coughing up blood.”
Getting the diagnosis two years ago has made a big difference to Becky’s health.
She has already gained between three and four stones and her lung function has increased by 45 per cent.
She takes medication, does physiotherapy and has breathing exercises for her lungs.
Karen, of Shaw Hill Street, Chorley, said: “She has dealt with it better than anybody.
“She is a typical teenager though and doesn’t want to be taking lots of tablets and spending her time doing physio.”
The CF causes Becky to have chest infections and she can find it hard to breathe.
It also causes digestive problems, so Becky struggles to put on weight.
She has also recently been tested for CF-related arthritis, as she suffers pain in her joints and hips.
In the future, Becky could even require a lung transplant if the condition develops.
Karen said: “She is fine at the minute, but her lung function could drop tomorrow or in five years or in 20 years.
“Some people die young and some people get to old age, it just depends on what CF does to them.”
Becky was initially diagnosed with asthma at the age of four.
A heel prick blood test now used to screen for CF in babies was not available when she was born.
Karen said: “They do regularly test newborn babies for it now.
“Becky suffered with not being diagnosed because she has always been ill, always been tired and always been small.
“She has missed out on a lot because she hasn’t known and hasn’t been treated for it.”
Becky, who enjoys spending time with friends and playing piano, now raises money for the Cystic Fibrosis Trust with her mum.
Earlier this month - on Becky’s 16th birthday - they did a sponsored walk from Hartwood Hall, in Chorley, to Blackpool Pleasure Beach with friends and family.
And on August 24, they will hold a family fun day with bouncy castles, stalls and other attractions at Broad Clough Farm in Bacup.
Karen, who held a ghost hunt last year, said: “I fund-raise because there is no cure and as I can’t take it away for Becky, I can do this to help her and all the other cystic fibrosis sufferers out there.
“I’m so proud of how brave she is even when she’s ill and in hospital and for how far she has come.’’
To support Karen and Becky’s fund-raising, go to www.virginmoneygiving.com/karenwinstanley1976.