Danielle Andersen was told her headaches were likely caused by dehydration09:03, 08 Jul 2026A teenager brushed off her persistent headaches as dehydration during a heatwave — but they turned out to be a warning sign of a ruptured brain tumour. Danielle Andersen, 17, had suffered the pain for five days before she finally made her way to A&E in July 2025.A consultant spotted something abnormal in her eye tracking, and a CT scan uncovered a slow-growing brain tumour known as a dermoid cyst — a benign growth. She underwent a craniotomy to have the tumour removed, but was left paralysed down her left side in the aftermath of the operation.It later emerged that she had suffered a stroke during surgery after three blood vessels were severed. She spent almost two months in hospital undergoing physiotherapy, and now, six months later, has made a remarkable recovery — able to jump and dance once more.Danielle, a student from West Wickham, London, said: "I thought it must be a dehydration from the heatwave, and everyone else told me that. But no matter how much water I drank, the headache wouldn't go. I was going to the toilet constantly because I was drinking and drinking."She added: "I was in pure agony. A lot of people didn't believe how bad it was. I kept thinking, 'am I making this worse than it is?' My gut feeling was that it wasn't just a dehydration headache though, and I was right.", reports MyLondon.Danielle's dad, Justin, 55, rushed her to A&E at Princess Royal University Hospital in Locksbottom on 17 July 2025, where doctors initially suspected a migraine. However, a CT scan revealed the dermoid cyst — which medics believe had been present since birth.Justin, a taxi driver, said: "Nobody sat us down and explained what any of it meant. We honestly didn't know the seriousness of it. We thought it was over - we thought it was just going to be resolved there."As Danielle, who has been dancing since the age of seven, had just landed a coveted spot at a London performing arts college, she opted to postpone her surgery so she could settle into her first term. She was referred to King's College Hospital at Denmark Hill, and the family were told the procedure carried odds of 100 to one against anything going wrong."I didn't want to go in as the person with a brain tumour," she said "I just wanted people to know me."She attended every single class without missing a day and was still dancing the week before she was admitted on December 15, 2025. When she woke up from the craniotomy, surgeons noticed her left arm failed to rise when removing her breathing mask.The family were told it was a "bit of weakness" that would clear up within days.But four days later, Danielle was completely paralysed down the entire left side of her body. Her right eye remained shut, her head drooped to one side, and she couldn't move her arm, leg or hand.An MRI scan revealed that during the operation three blood vessels had been severed, causing a stroke. It was three days before Christmas."We had been told she'd be home by the 22nd of December," Justin said. "We didn't leave the hospital until February 19."Medics informed the family they were uncertain whether Danielle would ever dance again, and told them she was unlikely to recover full function in her left hand."We weren't going to accept that her dreams and her life had gone down the toilet," Justin said.Her recovery demanded the brain reconstruct its neural pathways to the left side of the body, a process known as neuroplasticity. During the initial weeks, relatives would physically manipulate her toe, foot, knee and arm, repeating each movement a hundred times daily alongside NHS community physiotherapists and a private neurological physiotherapist."The physios said Danielle is only getting through this so quickly because her whole family is on board," Justin said. Six months later, Danielle has begun running, jumping, and is taking up dancing once more.She withdrew from her first year to concentrate on her recovery and is resuming in September alongside her younger sister Charlotte, 16, who has since earned her own place at the same college."My physio is just turning into dancing again," Danielle said. "Before, people had to move my arm because I couldn't move it. Now I'm dancing."The family are now raising funds through GoFundMe for intensive private neurological physiotherapy. Standard NHS stroke rehabilitation focuses on everyday functional recovery, but specialists say a dancer requires six hours of rehabilitation daily - far beyond what the NHS can deliver.To donate to Danielle's fundraiser, visit https://www.gofundme.com/f/cycufygKing's College Hospital was contacted for a response.