Sir Chris Hoy and wife Sarra are expecting their second child

Olympic cyclist Sir Chris Hoy and wife Sarra are expecting their second child together.

Sarra made the happy announcement during an appearance on ITV's Lorraine, where she was speaking about her ongoing involvement with premature baby charity Bliss after welcoming the couple's first child, son Callum, 11 weeks early.

'I think time heals, time gets you better, and actually – I’m pregnant,’ she told host Lorraine Kelly, who replied: 'Oh fantastic! I thought you might be… you had that look. You look fantastic and glowing and your eyes are sparkling.'

Later in the show, Lorraine presented the mum-to-be with a children's bicycle, joking: 'You have to take this home to him and say "you're going to get a baby brother or sister but here's a bike!"'

'A huge congratulations to Sarra Hoy, wife of Olympic cyclist Chris Hoy, who has just announced she's pregnant with her second child! 🍼😀' the show wrote alongside a subsequent Instagram snap of Lorraine and Sarra together. 'Callum is going to make a wonderful big brother! We hope he enjoys his new set of wheels! #SarraHoy #ChrisHoy #cyclist'

During the interview, Sarra said that the pair were 'so excited' to meet their new arrival, explaining: 'I would never have thought that I would have ventured down the road again, but actually time's a great healer and actually we're so excited about it.'

'The point is, prematurity or having a sick baby, it's unexpected for most people. So that's the shock of it. It might not happen again, but we'll see.'

Sarra and Chris welcomed Callum via emergency caesarean in October 2014, after she was diagnosed with preeclampsia and HELLP Syndrome.

Speaking at the time, Sarra, who works as a lawyer, admitted that the experience was 'terrifying'.

'I barely had a bump. I wasn’t even in maternity clothes. It had been a very healthy pregnancy but I'd been in hospital feeling slightly unwell the week before and then suddenly we were told he had to come out.'

However, she added that Chris was her rock throughout the ordeal: 'I have to say Chris was amazing and was my absolute support.'