A "fit and healthy" dad-of-two suddenly died on Christmas Day from an undiagnosed brain aneurysm.
Just hours prior, legal executive Mark Cox, 38, was dressed in matching pyjamas with his wife Tracey, 36, and their two children, aged 12 and nine, as the family played games on Christmas Eve.
At 6am the next morning he awoke at his home in Tonteg, near Pontypridd, Wales, with a severe pain in his head.
Tracey realised how serious it was and called an ambulance, administering CPR while waiting for the paramedics to arrive.
Mark, who worked as a completions manager for a solicitors firm, was then rushed to the University Hospital of Wales in Cardiff where he later died due to a brain aneurysm.
The dad - who didn't smoke nor drink - had no signs of illness in the run-up to his family Christmas.
"It was a complete shock. Mark was pretty healthy and never smoked or drank. It was completely out of the blue," his younger sister Natalie Nash said.
Natalie had formed a Covid-safe bubble with the young family so she could spend Christmas Day with them.
"It's just heartbreaking," she said.
"Mark was loved by so many people - he was so kind and caring and had so many friends."
She has now launched a GoFundMe page to raise money for Tracey - who had been with Mark for 15 years and married to him for 10 years - and the children.
Her target of $12,000 was passed by Monday morning with tributes from shocked well-wishers.
"The family are distraught,” the GoFundMe page states.
"Mark was loved by all that met him; he was kind, caring, funny, sociable and the wittiest person I knew. He was a crucial part of our family and will be missed so much.
"My sister, Tracey and her young children, Lily and Connor, who had their worlds completely turned upside down this Christmas. This year has been unbelievably tough and we want to make sure they know that they have as much support as possible during this horrific time.
"It's to cover any funeral costs or other bills. I just wanted to take away the financial burden. Tracey has been overwhelmed with the support and kindness she's received from people and can't thank them enough."
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