Olympic-winning cyclist Chris, 38, said Callum, who is his first child with wife Sarra is 'healthy, happy and doing fine' in a new interview with the Daily Record.
"It was such a surprise when he arrived 11 weeks early. Neither Sarra or I were expecting that" said proud dad Chris.
"He was in incubators, intensive care. But he's doing really well now. He's healthy, happy and doing fine.
"He just needs to gain weight, that's all. He has tripled his body weight since he was born. He is still very small, he's only about seven pounds."
Today was Callum's due date, but he arrived 11weeks early. Amazing how far he's come since then, we're so thankful. pic.twitter.com/1sbfrpot2j
- Chris Hoy (@chrishoy) December 27, 2014
Callum spent several weeks in hospital after his early arrival last year, but he was allowed home just in time for Christmas - and his Olympian dad has admitted his son has changed him in 'many ways'.
"You have a different perspective. You realise the things that are worth worrying about, the things that aren't," he told the paper.
"Everyone says that once you have kids, you never stop worrying.
"There's always something to worry about, no matter what age they are - 18 months or 18 years.
"You do start worrying about the things that are important."
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