Emerald Green by Kerstin Gier

When Gwenyth, a young girl in her teens, discovers that she has the time travelling gene and not her brilliant cousin, Charlotte she's in shock and unprepared. But, if that wasn't enough, she an her time-traveling partner, Gideon, must solve a mystery. A mystery that is yet to be deciphered. A mystery of how and why her other cousin, Lucy, and her husband, Paul, have disappeared into the past. A Mystery that involves who to trust and who to not. When Gwenyth feels like she finally has found all the answers, she always finds a new problem to solve one that involves death, sacrifice, and most of all, love. I recommend this book to teens, ages 13-16. Madeleine Y., Grade 6