When my sister started kissing
(Book)

Claire and Abi have always loved their summers at the lake house, but this year, everything's different. Dad and Pam, their stepmom, are expecting a new baby, and they've cleared out all of Mom's belongings to make room. And last summer, Abi was looking at boys, but this summer, boys are looking back at her. While Abi sneaks around, Claire is left behind to make excuses and cover up for her. Claire doesn't want her family to change, but there doesn't seem to be a way of stopping it. By the end of their time at the house, the two sisters have learned that growing up doesn't have to mean their family growing apart. -- from Amazon.