Kailyn gets into a fight with Jo and Chelsea fears she is pregnant again in the Season 4 opener.

Source: MTV

Kailyn and Jo go to court; Chelsea attends her first day at beauty school; and Jenelle learns that Gary slept with her best friend.

Source: MTV

Leah has trouble choosing between Corey and Jeremy; Jenelle finishes her probation; and Kailyn takes Isaac to see Jo.

Source: MTV

Kieffer and Jenelle get back together; Kailyn tries to change her custody agreement; and Jeremy confronts Corey.

Source: MTV

Leah makes a decision; Jenelle gets into a fight with Kieffer; and Kailyn and Javi take their relationship to the next level.

Source: MTV

Kailyn loses her cool with Javi; Gary and Jenelle get back together; and Leah makes wedding plans.

Source: MTV

Leah and Jeremy get married; Adam tries to make Chelsea jealous; and Gary reveals a surprise to Jenelle.

Source: MTV

An argument erupts between Gary and Jenelle; Leah moves into her new house; Chelsea seeks legal advice; and Kailyn and Javi consider getting married in Las Vegas.

Source: MTV

Jenelle goes to court; Leah reaches out to her biological dad; Javi and Kailyn discuss marriage; and Chelsea takes a break from school.

Source: MTV

Leah and Jeremy get married; Jenelle reveals her financial troubles; and Chelsea celebrates her 21st birthday.

Source: MTV

Chelsea celebrates Aubree's third birthday; Jenelle learns she has a slim chance of getting custody of Jace; Leah takes Ali to a specialist; Kailyn tells Jo about her plans with Javi.

Source: MTV

Kailyn and Javi get married; Chelsea returns to beauty school.

Source: MTV

Additional footage from the third season.

Source: MTV

Jenelle discusses her battle with addiction; Kailyn is encouraged to make peace with Jo's girlfriend.

Source: MTV

Maci discusses the status of her relationship with Kyle, and Gary reflects on his journey with Amber in the conclusion of this series-finale special, hosted by Dr. Drew Pinsky. Also: Leah, Bentley and Sophia share the stage one last time.

Source: MTV