The summer I turned pretty - Jenny Han

Belly is on the way to Cousins, with her brother Steve and her mother Laurel, like every summer. They stay in a beach house with her mother's " blood sister" Beck (Susannah) and her two boys Jeremiah and Conrad. Belly fell in love with Conrad like a thousand years ago, but he didn't noticed, but this summer it will change.
Belly is finally 15 years old and she has growen up, she's a real women now, and not only the little girl in the house. After a few days she realized that she's still in love with Conrad, but he has changed. He stays in his room all the days playing his guitar, he quit football, he started smoking..
But one day she mets on a party her dreamboy, Cam. They spent the whole summer together and Conrad seems to be a bit jealous. Finally, Cam sees that beetween Conrad and Belly is something, so he break up with her.

The summer end cames nearer and after a kiss with Jeremiah, Conrad noticed that he LOVE Belly, that he always did and they fortunetly come toguether at the end.