Sophie Ellis-Bextor would have been "crazy" to have planned to have a fifth child.
The 39-year-old singer is delighted she and husband Richard Jones are expecting a sibling for their four sons, Sonny, 13, Kit, nine, Ray, five, and Jesse, three, but she admitted she hadn't been trying to get pregnant.
Speaking on 'Jeremy Vine', she said: "People asked me if I planned it - I'm not that crazy but it was definitely a happy thing."
Although the 'Murder on the Dancefloor' hitmaker's home life is "chaotic", she likes having a large brood because she grew up as part of a big family.
She said: "I'm pretty relaxed, its family life it's chaotic and we're happy and I really like how I grew up with lots of brothers and sisters
Sophie married The Feeling bassist in 2005 and she admitted they both knew instantly they had found the right person.
She said: "From a dating point of view we're very fast - but you know we knew, within three months of meeting him. We're both quite speedy, when you know you know."
The British pop star announced her pregnancy news on Chris Evans' BBC Radio 2 Breakfast Show in August, describing the impending arrival of her fifth baby as "mental".
During a chat about her new album, 'The Song Diaries', Sophie casually shared: "The album will come out around the same time as my fifth infant because I'm having my fifth baby. Mental!"
She added: "You get more relaxed with the chaos ... says the woman who just ... we just went away Richard and I with five kids, because our eldest brought a mate, and I took a book which seemed like the most optimistic thing I could have done!
"It didn't even get open - that's without baby."
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