She was a bridesmaid at her mother and Patrick's wedding.
Andrea had started elementary school, with her best friend named Tammy. Andrea, who became suspicious after continuously noticing Buddy's shadow passing by her window at night, followed him to the Putter home the night of Emma's party, where they spotted Buddy with Molly (the Putters' female Golden Retriever) and realized that Buddy had been sneaking around at night because he was in love with Molly, eventually learning they were expecting puppies. Later, Andrea, Tammy, Emma, Josh and Buddy rescued the puppies from Snerbert and Webster.
Out of sadness, Andrea didn't go to the bus stop to say goodbye to Josh before he left for college, but with the help of Buddy, she managed to get to stop the bus in time to say goodbye.
Starting her first year of middle school, Tammy and Andrea struggled to find an activity to join before both settle on trying out for the baseball team. Tammy was a natural but Andrea struggles at catching and hitting, running the risk of being cut altogether until Tammy, without Andrea's knowledge, convinced Coach Crenshaw that her and Andrea are best friends and if Andrea was cut, she wouldn't play either. Andrea became frustrated when she was benched for most of the season until Randy accidentally hit Tammy in the right elbow with a wild ball causing an injury and leaving her unable to play and Andrea replaced her. However, Andrea's first game in the season resulted in her running into Randy while trying to catch a pop-up fly, causing them to drop the ball and their opponent to win. Andrea came home and found that Josh's old room was being converted into a nursery for her baby brother Noah and mentioned to her mom that it felt like she and Josh were being replaced by the new baby, but her mom convinced her that it was not the case.
Andrea continued to struggle on the team and overheard Tammy confessing to Randy the deal she made with Crenshaw when Randy wondered why Andrea was on the team even though she was terrible. Andrea wanted to give up on baseball until Buddy persuaded her to keep practicing, where she became better at hitting and catching. Andrea became the Timberwolves' pitcher and Buddy played first base (where Buddy was also revealed to be a great baseball player as well). Andrea and Buddy managed to send the team on a winning streak, but the day of their championship game, Carlton and Professor Siles kidnapped Buddy, with Tammy and Andrea in pursuit, rescuing Buddy, Zack, Striker, Shooter, and Duke before experiments could be conducted on them. The Timberwolves struggled without their three star players, but they managed to come back from behind to edge out their rivals, the Baboons, in a 8-7 game, when Andrea scored a double hit.
When Noah was sad about the Buddies having to leave to live with new owners, his father told him it was their time to leave, just like when it was Josh and Andrea's time to go to college.