The TV presenter Tweeted her sadness, but said Belle still had a great time.
She wrote: "Thanks for all the birthday tweets for Belle! Unfortunately I'm In hospital but her dad tell me she's had a lovely party x."
She later added: "Hoping tomorrow will be discharge day from hospital for me. 7 days without my daughter - feels so cut off!"
Katie, 31, was the victim of an horrific acid attack in 2008 by her ex-boyfriend, and has had to have regular procedures since.
She had been due to celebrate with her daughter and her fiancé but had to stay in hospital.
A source told the site: "There was a slight side effect to the procedure causing the oesophagus to tear and causing air to leak into her body which is obviously very dangerous. She's stable now but sadly had to miss her daughter's first birthday."
No doubt she will be planning belated celebrations with Belle - though perhaps more laidback than this first birthday party.
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