Susannah Leah, 12, won a Blue Peter competition to design part of the iconic time travelling device, and will see her dream turned into reality when her sketches are made into a prop, which will be shown in an episode of the new series of BBC1 television's Doctor Who.

The Todmorden High School pupil saw off competition from thousands of other entrants, and as part of her prize will be travelling to Cardiff tomorrow to visit the Doctor Who set, meet the new Doctor, actor Matt Smith, and see how the show is made.

Susannah said: "I was watching Blue Peter at my grandma's house and I saw the competition and I thought 'that would be fun', because I like designing and art and things. It took me about a day to finish the drawing.

"When I found out that I'd won I just started smiling and was really happy and shocked.

"I'm excited to meet Matt Smith. I hope he's good as the new Doctor.

"I'd love to work on the Doctor Who set in the future. It would be so cool."

Susannah lives with her mum Janet, dad Mark and brother James, and her mum - who will be accompanying Susannah down to Cardiff - found out that her daughter had won a week before it was officially announced.

She said: "We're really proud. She has always done art. She's always had good ideas since she was little. The lady who has been organising everything rang me and said that Susannah had won - but she wanted to keep it a secret.

"So I had to keep it a secret for a whole week. Mark kept humming the Blue Peter theme tune all week because he's a bit of a joker like that!

"We went up to Leeds to go ice skating and told Susannah that she was there for a photo shoot and when she got there it came up on screen that she had won."

As well as visiting the set today, Susannah will return at a later date to assist the production team with the development and manufacture of the prop.

The prize also includes receiving a framed copy of the design, signed by Matt Smith, and two Blue Peter badges, one for entering and one for winning.