<P> Frank reveals that he never liked camping anyway, and decides not to send Greg to Spag Union, much to Greg's surprise and delight . Frank gives Greg advice about learning from mistakes and taking responsibilities . The two discover they are much alike than they realize . </P> <P> At Heather's Sweet 16 birthday party a few days later, Löded Diper performs a hard rock version of "Baby" by Justin Bieber and Ludacris, during an attempt to win over Heather . However, Rodrick accidentally knocks over a huge ice sculpture of Heather, which results in her losing her temper and accidentally smashing a chocolate fountain with a microphone stand, splashing chocolate all over her, and the party ends in disaster . </P> <P> Holly then implies that she likes Greg by holding his hand, and in the final scene, Greg, Holly, and Rowley all hang out together at the local pool . Greg describes that his summer did not go the way he expected, but had positive circumstances . </P> <Ul> <Li> Zachary Gordon as Gregory "Greg" Heffley </Li> <Li> Robert Capron as Rowley Jefferson, Greg's best friend </Li> <Li> Devon Bostick as Rodrick Heffley, Greg's brother </Li> <Li> Rachael Harris as Susan Heffley, Greg's mother </Li> <Li> Peyton List as Holly Hills, Greg's love interest, friend and eventual girlfriend </Li> <Li> Grayson Russell as Fregley, one of Greg's weird classmates </Li> <Li> Karan Brar as Chirag Gupta, one of Greg's friends </Li> <Li> Laine MacNeil as Patty Farrell, Greg's arch - enemy </Li> <Li> Steve Zahn as Frank Heffley, Greg's father </Li> <Li> Melissa Roxburgh as Heather Hills, Rodrick's love interest and Holly's older sister </Li> <Li> Connor / Owen Fielding as Manny Heffley </Li> <Li> Alf Humphreys as Mr. Jefferson, Rowley's father who dislikes Greg </Li> <Li> Bronwen Smith as Mrs. Jefferson, Rowley's mother </Li> <Li> Terence Kelly as Grandpa Heffley, Frank's father and Greg's grandfather </Li> <Li> Oliver the Dog as Sweetie Heffley, the Heffley's new dog and addition to the family </Li> <Li> Phil Hayes as Stan Warren, Frank's boss </Li> <Li> Jeff Kinney as Mr. Hills, Holly's father </Li> </Ul>

Who plays bill in diary of a wimpy kid