Christie Brinkley is back in her Hamptons home preparing for her big birthday party – which will take place on Tuesday.MORE: Christie Brinkley's $29.5million home is basically a luxury retreat – see insideThe mother-of-three will be making an appearance on QVC on 2 February to celebrate her special day with fans, who will be able to get their hands on the model's organic, vegan, zero sugar, and zero carb Prosecco.Christie has been promoting the show since she left her Turks and Caicos holiday