Kinney Jeff Kinney 
Ugly Truth (Diary of a Wimpy Kid #5) 

Greg Heffley has always been in a hurry to grow up. But is getting older really all it’s cracked up to be? Greg suddenly finds himself dealing with the pressures of boy-girl parties, increased responsibilities, and even the awkward changes that come with getting older-all without his best friend, Rowley, at his side. Can Greg make it through on his own? Or will he have to face the "ugly truth"?