It looks like both Dr. Sheldon Cooper and his roommate Dr. Leonard Hofstadter are in big trouble, since their mothers are going to be paying a visit in the April 30 episode.

Mrs. Mary Cooper and Mrs. Beverly Hofstadter, played by Laurie Metcalf and Christine Batanski, respectively, will be working together on a single episode for the first time, Fox News reported.

The two mothers could not be more different. While Mrs. Cooper is deeply religious and doting, Mrs. Hofstadter is a super genius who is aloof and unloving towards her own son Leonard, whom she considers a "disappointing child."

In fact, it was Sheldon who formed a good connection with Mrs. Hofstadter, and he and his roommate's mother communicate more frequently than she does with her own son.

No details have been revealed yet about the episode's storyline. It would be nice to see the boys reuniting with their mothers, since their friend Howard Wolowitz just lost his own mother Mrs. Debbie Wolowitz after the actress who voices her, Carol Ann Susi passed away last November.

Metcalf's Mrs. Cooper last appeared in the show's season 7 episode 13, while Baranski's Mrs. Hofstadter made her last appearance in the show's season 7 finale.

Meanwhile, Howard might have just lost his mother, but the show will soon introduce his long-lost younger brother Josh Wolowitz in "The Fortification Implementation" episode.

Josh will pay a surprise visit to Howard during the episode, and he will be played by former Nickelodeon star Matt Bennett. Josh's arrival is guaranteed to stir up a lot of emotions on Howard's end, especially since his father left their family when he was only 11 years old, and they have remained estranged.

In the episode "The Closet Reconfiguration," Sheldon came upon a letter from Howard's father while he was cleaning his closet. Howard said he half wanted and did not want to find out the contents of the letter, so his friends came up with the idea of telling him different stories about the letter, and only one of the versions is correct so Howard got his wish.

It is unclear whether Josh will be a recurring character in The Big Bang Theory as well.

For that same episode, Wil Wheaton will be back and he invites Penny to join in his podcast, resulting to a fight between her and Leonard. Sheldon and Amy will build a blanket fort and "come to major crossroads in their relationship," according to CBS.