Heading into its 10th season this fall, CBS' The Big Bang Theory is more popular than ever. Yesterday at Comic-Con, the show held its annual panel, where they announced two huge guest stars, Kaey Sagal as Penny's (Kaley Cuoco) mother Susan, and Jack McBrayer playing Penny's brother Randall, an ex-con drug dealer. Both characters will be introduced in the Season 10 premiere. Along with that intel, another interesting detail about one of these fan-favorite characters was also revealed during this panel.

The panel was moderated by cast member Melissa Rauch, who plays Bernadette on the hit series, and featured the show's writers and executive producers Steve Mollaro, Bill Prady and writer Steve Holland. During the Q&A portion of the panel, Melissa Rauch was asked about Bernadette's unique voice, and if that was something that was specified on the page when she first read for the role. The actress revealed that the distinct voice was something that she brought to the role personally.

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"That was something that I came in with on my own. That was something I did in the audition and then ran with it. That's actually my real voice and this is my fake voice."

TV Line also spoke with Steve Mollaro, Bill Prady and Melissa Rauch, where they got some new details about when we'll meet Penny's mother and brother. Fans have already seen Penny's likable Dad Wyatt, played by Keith Carradine, in the past, but Steve Mollaro revealed why, and when, we'll meet Susan and Randall. Here's what he had to say below.

"The season premiere will be picking up the night after the final episode of Season 9, so we left it that Penny and Leonard were going to be doing a re-do wedding for their family and friends, because they had eloped. So they're coming to town for this re-do wedding, along with Penny's brother, who we had heard throughout the years had been in and out of jail for selling drugs. Of course, when you think of somebody mean and scary, you go and get Jack McBrayer. We couldn't be more happy about that. So the first time we meet them as a family, Penny is driving them back from the airport, her dad, her mom and her brother Randall."

The producers also teased that Bernadette will start to show her baby bump in The Big Bang Theory Season 10, while confirming that the birth will happen this season on Big Bang. They also talked about the speculation that this may be the show's final season, but nothing has been set in stone yet. Take a look at this video interview with Steve Mollaro, Bill Prady and Melissa Rauch from The Big Bang Theory.