The eighteenth episode of "The Big Bang Theory" Season 7 is titled, "The Mommy Observation." The episode will feature the meeting of Sheldon and his mother. In the previous episode, Howard asked Sheldon to come with him to a tour of NASA in Houston. The new episode will show them in Houston, after a turbulent plane ride.

According to the spoiler leaked online, Sheldon arrives at his mom's place, unannounced, and gets surprised. The spoiler suggests that he will see his mother with a naked man. This will jolts him and Howard will be there to provide advice, without any pun. He will ask Sheldon to talk to his mother.

The spoiler indicates that Sheldon and his mother's talk will not end on a positive note, as they will end-up fighting. Howard will again wear his wise, good friend hat, telling Sheldon about how his father left his mother and him, and then another guy left his mother, as well. This will lead to a proper conversation between Sheldon and his mother.

At 4A Apartment, the rest of the gang will be playing Raj's Murder Mystery game. Stuart will arrive at the apartment and drop dead. The game will make the gang discuss where they will be in 20 years. According to the spoiler, Raj thinks that Amy will win the Nobel Prize. She will also buy Stuart's comic store and sell it, so that Sheldon will pay more attention to her. In 20 years, Penny will be an actress in London, while Leonard will be a famous scientist in the U.S. The two will not be together. Stuart, however, does not think that Leonard and Penny will separate. Meanwhile, Raj thinks that he will be married to Beyonce.

The gang also plan to meet in 20 years for dinner. The flash-forward, according to the spoiler, will show only Stuart turning-up for the dinner meet.

Official Synopsis of "The Big Bang Theory" Season 7 Episode 18, "The Mommy Observation": "When Sheldon visits his Mom in Houston, he is forced to confront a new reality. Meanwhile, Raj's 'Murder Mystery' party starts some fights within the gang."