The 26-year-old model, who gave birth to daughter Sophia with her footballer husband Peter Crouch last year, posted a photograph of the little girl on her Twitter page to celebrate the landmark day.
Clancy wrote alongside the image: "Here she is little birthday girl 1 today x." She later wrote: "So sad I am got all teary reading ur lovely messages about my baby she is so cute though a little pudding ha x (sic)."
Although Sophia's birthday was yesterday, Clancy and Crouch threw her a birthday party earlier this month. At the time, she wrote on the microblogging website: "Organised a mini farm for Sophia's birthday they come to the garden pigs lamb lama Shetland pony bunnies goat sooooo excited x."
Yesterday, she described her daughter as a "princess" because she was getting to have two birthday celebrations.
Last year, Clancy admitted that she wants Sophia to be a singer when she grows up, saying: "She's very musical and loves playing the tambourine - she has daily music lessons... I'd be happy for her to be a popstar."
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