More of Penny's family will be featured in the upcoming season of "The Big Bang Theory" when the show returns for its tenth season.

In a report by Entertainment Weekly, promo shots gave fans a sneak peek into Penny and Leonard's garden wedding. The lovely bride is being walked down the aisle by her dad Wyatt (Keith Carradine) with everyone looking on happily- except for Sheldon.

According to Executive Producer Steven Molaro, the happiness of the characters in the scene was an exact reflection of the fun they had while filming the episode. "Johnny Galecki texted me more than once from the soundstage just to say they were simply having the greatest time. Everybody was having a blast," he said.

The showrunner also hinted at some tension among Penny's family that will be revealed in the upcoming season. According to Molaro, while Penny has always been close with her dad, her relationship with her brother is another story altogether since Penny's mom Susan (Katey Sagal) and her brother Randall (Jack McBrayer) used to sell drugs.

The EP further said that they would like to explore the story of Penny and her family further into the season to give Sagal and McBryer more time to develop their characters.

"Every character on the show has something great to do. Now that they are officially members of the Big Bang family, we would love to have them come back so we can service them with more time and energy than we could in the premiere," he said.

Meanwhile, aside from introducing more family members to the show, "The Big Bang Theory" is set to welcome a superhero guest for season 10, who is none other than The Flash.

"He appears in one of Sheldon's dreams. He does insane things. It's a Flash we may not be used to," Molaro added.

Meanwhile, Sheldon and Amy will also show a progression in their relationship as they move in together. However, the move will be viewed mainly as a science experiment to get Sheldon on board with the idea.

The Big Bang Theory returns to CBS on Monday, Sept. 19, at 8 p.m. EDT.