The spoilers I remember are as follows: The protagonist is actually the cousin of the popular girl in school, and is actually close in age to her. The protagonist's father had forged a birth certificate in an attempt to distance the protagonist from the curse. Basically the curse is that every other generation a girl ~16 years old in the family dies. Because of all this, the popular girl's family tries to kill the protagonist on the night the curse is supposed to happen (I think it coincided with Mardi Gras?) so the popular girl would live. However, the popular girl ends up getting killed (gruesomely) due to a statue falling on her head. In the end the ghost moves on, as this was supposed to be the end of the curse, and the protagonist helps do community service stuff with a boy she met earlier in the novel.