The Big Bang Theory Episode 7.18 The Mommy Observation

Sheldon and Wolowitz are still in Houston and Sheldon decides to surprise his mother with a visit. When they get there, Sheldon looks in the window, sees his mother having sex, and leaves before she sees him. Wolowitz convinces Sheldon to go back and talk to his mother but Sheldon only ends up insulting her. Wolowitz then tells Sheldon how he faced a similar situation with his mother in the past, and that Sheldon shouldn't stand in the way of his mother's happiness. In the end, Sheldon goes to talk to his mother and ends up giving her a lecture about safe sex. Meanwhile, the group is back at the apartment eating Thai food when Stuart collapses and seems to die. It turns out to be the set up for another one of Koothrappali's murder mystery games that everyone dislikes. Koothrappali has written down scenarios for where everyone is in 20 years and it turns out Penny and Leonard are living in different cities. This leads to a meaningful conversation about what their future holds.