Corey surprises Leah with a marriage proposal, but things get hard when an eye doctor tells her Ali's development problems may originate in the brain. Chelsea tries to shift her focus back to school, while Kailyn gets a second job so she can move out... (more) on her own. Jenelle and her boyfriend Kieffer wear out their welcome at a friend's house and have to find a place to live while Jenelle begins college.