She said: 'When I got the part I wasn't allowed to say anything about it to my friends until it was official. I had to wait three months, which was really hard.Then when I finally told them, they couldn't believe it. They are really supportive and proud of me.'

She said: 'The first time I met Daniel, Rupert and Emma I was actually doing a drama workshop with them.

'That was really intimidating because I was asked to improvise, do some drama and act a bit.

'But it was cool because when we spoke afterwards they told me not to worry about it and it would be great fun.'

Katie said: 'My favourite scene is probably the ball because we got to dress up, put on make-up and get our hair put up and everything.

'But the whole acting process has been really magical with this film and it's like a dream come true when you walk on to one of the sets.'

She explained: 'Cho Chang is a girly girl. She likes skirts and I am much more of a tomboy. I like trousers and jeans, whatever is comfortable.

'I love music and like to play the piano. I started when I was younger, but I had to stop for education and other stuff. I definitely want to get back to it though when I get some spare time. I love to shop and go to cinema too, you know, all the usual stuff that a seventeen-year-old likes.'

Katie said: 'All the girls bonded together and then there were the boys. Girls like to gossip.

'I am good friends with all the new cast as well because we are all new here."