Toy manufacturer Hasbro will exhibit Lucy's design in New York on September 18.

Lucy's mother Narelle Dart said her daughter had won two return flights to New York and seven nights' accommodation with $1000 spending money.

"The main thing is we're there on the 18th because that's My Little Pony's 25th anniversary and the exhibition where they will launch Lucy's design," she said.

Mrs Dart said the win had surprised everybody.

"It just started as a Saturday morning activity. Lucy and her younger sister Olivia entered to design a pony. The pony is already drawn up for you so it's just a matter of adding whatever you want to it," she said.

"Lucy named hers Blueberry Delight and coloured the pony in purple with rainbow coloured hair. Then she put some ice-creams on it and she also put `Happy 25th Birthday' on her design.

"I think she had gone over the edges with the colouring a little bit, so she decide to cut the pony out and paste it on some pink paper and then added some flowers and butterflies."

Competition organisers told Mrs Dart last Wednesday that Lucy had won the grand prize.

She was so excited she told Lucy during recess at Nhill College.

"Lucy's teacher had her up the front to tell the good news to the class," Mrs Dart said.

"And everybody smothered her and the kids were hanging off her. Lucy actually cried for a moment when I told her, she was very emotional."

Lucy said she couldn't wait to go to the New York launch.

"I am looking forward to going to the main party where they will launch my picture," she said.

"It was a surprise when mum came to school to tell me."