Teen Mom 2 First Look: See Chelsea, Leah, Jenelle And Kailyn Back In Action

The long-running series returns March 21.

Chelsea's, Kailyn's, Jenelle's and Leah's stories are an open book -- and the latest chapters from the young mothers' daily lives will soon be showcased on Season 7 of Teen Mom 2. And when the long-running series returns in FIVE days (March 21, don't forget!), the unique cast members will encounter new challenges and endure some exciting firsts -- as evidenced in the four sneak peeks below.

First up, Chelsea's readying her mini-me Aubree for a major educational milestone: kindergarten. While the esthetician is understandably beaming with pride for her little lady (and even feeling some butterflies as if it's her first day of school), the new student is visibly looking forward to this educational endeavor.

Meanwhile, Kailyn has a photoshoot with her sons -- but the outing takes a sour turn when she gets into a fight with Javi about getting dinner with Jo and Vee (the Air Force man did not want to attend the meal and wanted the mother of two to bring home the toddler).

In addition, Leah and Corey take their daughter Ali to a doctor appointment relating to her muscular dystrophy diagnosis -- and the topic of her wheelchair use is raised. But the parents get some troubling news: When Ali turns seven, their child's strength will gradually deteriorate and she will slowly get weaker.

Lastly, relations between Jenelle and her mother Barbara start off cordial during a routine Jace pickup. But the conversation quickly escalates -- and a few tears are shed -- when the grandmother brings up her daughter's legal issues.

Stay with MTV News for more Teen Mom 2 updates, and be sure to watch the premiere on Monday, March 21 at 10/9c!