Adele Atkin and her sister Tanya were healthy young girls who loved adventure and were members of Portsmouth Northsea Swimming Club.
But six years ago that all changed when Adele began struggling to walk without falling over. Her problems became so bad that she had to give up swimming and would drag her foot when she walked.
Parents Kelly and Paul fought to get a diagnosis for her.
And within months of Adele becoming ill, her older sister, Tanya, began showing the same symptoms.
Doctors were baffled as to what was happening to the sisters, from Wymering, Portsmouth.
The previously healthy teenagers were soon having to use wheelchairs.
I am a really proud mother to four perfect childrenKelly Atkin
It seemed inexplicable to Kelly and Paul that both their daughters could suddenly fall victim to the same mystery condition.
In 2013, after four long years, they received an answer. The girls had hereditary spastic paraplegia, which showed itself because both Kelly and Paul are carriers.
It is rare and the couple’s other daughters, Jade, 13, and Tasha, 21, who has a different biological father, have not developed it.
Kelly, 38, says: ‘Adele began to fall downstairs, upstairs, through the door. She stopped being able to balance on her scooter, she fell off her bike, she fell off the blocks at her swimming club.
‘It was a slow, gradual heart-breaking time and Adele really used every ounce she could to remain walking.
‘She went to every appointment hoping for the answer. She had blood tests, MRI scans, lumbar punctures, nerve conduction tests, hospital stays for physiotherapy and investigations and an operation to release tendons.’
Kelly adds: ‘We have had tears throughout as no answers could be given.
‘We did have support from doctors, physiotherapists, occupational therapists and consultants.
‘But it is lonely returning home with no reason as to why your daughter is losing the ability to walk.
‘She would drag her body around and once fell through a plasterboard wall and was stuck in a heap on the floor, too weak to pull herself up. Having to carry your child around the house is heartbreaking.
‘In the meantime our physiotherapist kept asking me to get Tanya referred. It took a year because she has autism and a language disorder.
‘I thought “how can it be possible for her to have the same as Adele?”.
‘I stuck my head firmly in the sand but the big falls began to increase’.
Kelly continues: ‘It took almost four years to be diagnosed and my girls and family have gone through severe depression, loneliness and a feeling of being lost that anyone trying to find out what is medically wrong for that length of time will relate to.’
Dad Paul, 53, a security guard, says: ‘It’s been horrendous. Not only the physical, but the mental strain. They both have really black days and some days they just don’t see anything positive.
‘Tanya wasn’t far behind Adele. But because she is autistic as well it’s doubly difficult’.
Adele, who attends Portchester Community School, and Tanya, who is training to be a hairdresser, try to walk around the house, but it often ends in a fall and some tears.
Yet things have been on the up since last November, when Adele attended an activity session organised by the charity Enable Ability and was introduced to wheelchair basketball.
Kelly says: ‘At first she couldn’t even get the basketball near the hoop, but her coach saw something in her.’
She describes the joy of seeing her daughter’s face ‘light up’ when she scored her first basket.
Adele now trains three times a week with Aldershot’s Blackhawks. .
She has set her sights on the higher echelons of the sport.
Paul says: ‘She went and tried for the regionals. She just did it and I could not believe it.
‘But since the wheelchair basketball began she hasn’t looked back.
‘All the anxiety and stress went. She’d been home from school for so long that getting out there and meeting people was brilliant for her.
‘She’s doing really well. It’s been life-changing’.
Adele says: ‘Wheelchair basketball has made me a little bit more confident. I recently met up with some friends at Thorpe Park, which I could never have done before’.
The couple’s other daughters, Tasha and Jade, have been a huge support.
Kelly says: ‘Jade is 13 and she’s the little big sister. She is so grown-up and plays wheelchair basketball alongside her sister.
‘It’s lovely they can do something together again.
‘I do feel Jade has never really been able to be the baby of the family.
‘She makes me beam with pride because she gives life 100 per cent.
‘Tasha is 21 and at university. She is a very strong, determined, independent lady who I watch flourish and work hard to support herself.
‘She worries all the time about us. It’s just the caring nature that she has. I am a really proud mother to four perfect children’.