It is almost a month since Joe and Laura O'Brien lost their father suddenly in the most shocking way.
But they still speak of him in the present tense.
“You never think it's going to happen to you, it's still very surreal,” says Laura, 29.
On December 3, Carl was awoken in the night at his Sutton home by a constant ringing on his door.
He went outside, and was the victim of an unprovoked attack to the back of the head – by an unknown assailant.
Taken into, and later released from hospital, he felt unwell – being recalled he tragically died there of a brain haemorrhage on 23 December. He was 55.
The attack, which fell on the same day as his sole grandchild's first birthday, turned lives of his family upside down.
“You see your dad, who is a 6ft 4ins tall strong man deteriorate like that, and it's difficult to take in,” said Laura. “We don't want him to to be defined by that.”
Carl, who was known to perhaps hundreds of Chelsea fans as 'Wurzel' because of his crazy hair and similarity to Wurzel Gummidge, was a larger than life character – and not just physically.
A Chelsea supporter for 40 years – home, away, he was also known to many former players, having worked as a groundsman at Stamford Bridge in the late 1980s and early 1990s.
Generous, perhaps to a fault (“he'd always walk into a pub with a note in his hand”), the stories of his travel with the club reflected these traits: for example the time, on Champions League travels to Ukraine, when he left an 18-year old local barman desperate to see the match a ticket as a tip.
“The lad didn't really speak English, and they sat together throughout the game,” said Joe, 21.
Wurzel was a well-known face with 'Chelsea On Tour', visiting 20 plus countries.
He followed the side to the 1998 Cup Winners Cup final: driving to Stockholm, to see Chelsea beat Stuttgart.
On the club's greatest night, in Munich, he spent the hours following the game drinking with and consoling Bayern fans – until the sun came up.
Having experienced his first game in the 1960s, aged six or seven, against Sheffield Wednesday with his father – he was living the dream of Chelsea's unexpected, and long-awaited success.
After leaving the employment of Chelsea in the early 1990s, chasing a better wage to provide for his young family, he became postman for 12 years, and after that a courier.
Finally, he settled as a black cab driver – something which suited his 'free spirit',and enabled him to fit-in his trips with Chelsea.
Joe says London's tight-knit licensed taxi drivers have been particularly kind and helpful following his father's death, though the greatest support has come from the Chelsea community.
“I've got a lot of comfort from seeing things about dad since then. I can't believe the kindness there's been,” said Laura (who was given the middle name 'Chelsea').
Joe has been contacted by fan group We Are The Shed about producing a banner to honour Wurzel's memory.
When asked he would always say his proudest achievements were Joe and Laura: for many reasons, not least that they were the first generation of his family to go to university.
Because of the nature of his death, the family has yet to receive his body back from authorities, prolonging the heartache.
They hope to be able to plan a funeral in February, where his two passions of rock music (he saw Jimi Hendrix at the Isle of Wight Festival aged nine, and was smitten) and Chelsea, will be represented.
“We have good and bad days,” said Joe, “and the stories from other fans really cheer us up.”
There will be a celebration of Carl's life before the Hull match on Sunday, at a location near Stamford Bridge, with family and friends sharing drinks in his honour (Laura: “It's perfect for Dad, he'd so love that.”)
His picture will be on the big screens at half time, and then in the 55th minute – chosen to reflect his age when he was taken away, he will be applauded.
Joe will be in the Matthew Harding Upper, where he watched so many games with dad, to share the moment - which he says will be emotional.
Laura, who was unable to get a ticket for the match, will not be far away.
“He was a good man,” she said. On Sunday, a great number of people will stand up to publicly share the sentiments.
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