Teenage British Olympic diver Tom Daley's father Rob has died after losing his battle with cancer.
The 17-year-old's agent confirmed to BBC Radio Devon that Rob Daley, 40, had passed away on Friday evening.
"He died 14 months exactly to the start of the 2012 Olympics," said the 17-year-old Daley.
And he added: "I hope he will be watching and waving his big Union Jack in London from somewhere else. I love you so much dad."
Diagnosed with a brain tumour in 2006, Rob gave up his electrician's business to follow Tom to events around the world and watched his then 15-year-old son become Britain's first individual diving world champion when he won the 10m platform event in Rome in 2009.
Plymouth-born Tom followed that success with double Commonwealth gold in the 10m platform and 10m synchro event in Delhi in October 2010.
However, for the first time, Rob was not with Tom because he had been undergoing chemotherapy and doctors had advised him not to travel.
Rob, who had 80% of a fist-sized brain tumour removed in 2006, had been in remission until a routine health check in 2010 discovered a tumour had returned. He watched events in Delhi unfold on television and was phoned by Tom "within a minute" of him winning gold.
"Tom's father was very dedicated and would come and watch every training session," added Daley's coach Andy Banks.
"He never got involved in the coaching side of things but offered Tom his full support.
"Even if Tom wasn't performing up to his usual standard, his father would be really supportive. He was very much part of Tom's team and Tom wouldn't be where he is today without him."
Tom, who was with his father on Friday, wrote on Twitter: "I love you so much Dad."
And on Saturday, he added: "If I could be half the dad that my dad was to me then that would be my best achievement! I love you! Xx"
A British Swimming statement said: "Tom Daley's father, Rob Daley, lost his battle with cancer yesterday, 27 May, at 9.35pm.
"His health has been fluctuating since February but he continued to fight until the last day, defying doctors' expectations.
"The family have asked for respect to their privacy during this very difficult period."
David Sparkes, chief executive of British Swimming, added: "On behalf of everyone at British Swimming, I would like to express our condolences to the Daley family at this very sad time.
"We will be doing all we can to ensure the whole family has the right support structures in place to help them through this difficult time.
"Rob will be remembered as a dedicated father, a fan of diving and a passionate and effervescent character who will be greatly missed."
Several high-profile divers and swimmers have posted their own messages on Twitter.
Tom's 10m synchro diving partner Pete Waterfield said: "R.I.P Rob our thoughts are with you @TomDaley1994 love the Waterfield family."
And Australia's Olympic gold-medal winning diver Matthew Mitcham tweeted: "@TomDaley1994 my thoughts are with you *hugs*."
Britain's double Olympic champion Rebecca Adlington said: "My thoughts are definitely with @TomDaley1994 and his family at this horrible time! Such awful sad news. We're all here for you tom x."
Tom later replied to the well-wishers: "Thanks for all the lovely messages about my dad... he was a great husband, son and father! X."
Tom is one of Britain's best prospects for a medal at next year's Olympics and last October, in an interview for a BBC documentary, Rob said: "London 2012 is a massive motivation for me. Am I going to be there? Tom is the oil in my lamp and he's going to keep me burning."
Last month Rob defied his illness to watch Tom and his new synchro partner Waterfield win a World Series event in Sheffield.
Rob wore a T-shirt to the meeting which read "Give me oil in my lamp, keep me burning" with Tom saying after the event: "I am his oil."
Rob leaves his wife Debbie and three sons, Tom, William and Ben.