As Mason goes in for his 6-month check-up, Kourtney realizes she wants another baby so her kids will be close in age like she and Kim were, but when she obsesses about getting pregnant, Scott thinks she's taking all the fun out of the process of trying. Meanwhile, Bruce has a hard time accepting that 12-year-old Kylie has male friends, and there's tension when she breaks the rule about inviting a boy up to her room.