2 Books Found

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"a story about a girl who I think goes to live with a new stepsister named Lucy. Lucy has rainbow braces. Lucy and the girl become closer and ever=naturally run away from home together. the cover had a blonde teenage girl wearing a glittery dress that is an American flag. I think the text was orange, but I'm not sure. it was probably from late 90s, early 2000s. the girl on the cover was smiling, and I think it might have taken place in Australia"