It's a year of big changes for Leah, Jenelle, Kailyn and Chelsea on the exciting third season of Teen Mom 2. Each of our young moms is faced with their toddler's adventure into the 'terrible twos,' all the while confronting new sets of obstacles and challenges as they try to grow up themselves. In this season, southern sweetheart Leah must let go of Corey when they finalize their divorce. But when her new beau, Jeremy, steps into the picture, Corey confesses regret. After some back and forth, Leah realizes Corey is unwilling to try to win her back and she moves on. Quickly Leah not only announces an engagement to Jeremy but also shocks Corey with news that she's pregnant. Meanwhile, Jenelle is home from rehab and slowly falling into her old hard-partying ways. As she struggles to stay out of jail, she's also faced with the decision to find out who Jace's biological father is once and for all. Kailyn still has lingering feelings for her son Isaac's father Jo, but her hopes are put to rest when she finds out he has a new girlfriend, Vee. Kailyn tries to rekindle things with ex-boyfriend Jordan, but is more focused on Jo and Vee spending time with Isaac. After several court appearances, things seem to settle and Kailyn meets a new guy Javi. Finally, Chelsea is back in the tumultuous push/pull with her daughter Aubree's father Adam. This time he even gives her a promise ring, saying that they'll work through their issues, but after a fight with her dad Randy, Adam disappears.