One of the biggest mysteries of The Big Bang Theory will remain this way forever.
Penny's maiden name (played by Kaley Cuoco) has never been revealed and this is how it will stay, according to the producer of the show.
"(Eventually) we were nervous and superstitious at giving her one," Molaro said at WonderCon.
Penny married Leonard Hofstadter (played by Johnny Galecki) earlier in season 9 and Molaro said about the character's last name, "it will always be Hofstadter."
The 12th and final season of The Big Bang Theory is currently on the air in the United States and the last episode will air in May.
The show's writers told WonderCon staff that saying goodbye to the characters they created and who have been so close for years has been a difficult process, but they have received some friendly advice from Friends creator Marta Kauffman.
"Some of us were at an event and we saw it," said writer Tara Hernandez, according to The Hollywood Reporter.
Kauffman's advice to them was, "It's going to be very difficult for you, but you're going to fall in love with the next one, you have to fall in love with the next one."
Here are some fun facts you may not know about the Big Bang Theory.
KALEY CUOCO WAS NOT ON THE PILOT
Kaley Cuoco was not originally cast as a female lead in The Big Bang Theory.
She auditioned twice but lost the part to fellow Amanda Walsh.
However, after CBS gave the pilot episode down, creator Chuck Lorre decided to mix things up and invited Cuoco to come back and test the part again.
"Third time is the charm!" joked Cuoco to Vegas magazine about the paper landing.
THE PILOT HAS A COMPLETELY DIFFERENT THEME MUSIC
The theme song of the Barenaked Ladies Big Bang is iconic now, but it was not even the original choice for the show.
For the pilot episode, Thomas Doly's 1980 song, She Blinded Me With, was used instead – but clearly, it did not fit, and was soon replaced by the current song.
KALEY CUOCO AND JOHNNY GALECKI DATED FOR YEARS
Kaley Cuoco is close to all her Big Bang co-stars, but she is especially close to Johnny Galecki, who plays Leonard in the show.
"We dated for almost two years," she revealed to Watch! reviewed in 2010.
"It was such an important part of my life and nobody knew it. It was a wonderful relationship, but we never said anything about it and we never went out together."
"I'm so lucky it was a mutual ending and we did not hate each other. We saw it happen at other shows."
SHELDON SHIRTS OFTEN REPRESENT YOUR MOOD
Green Lantern fans are probably already aware of this, but for the rest of us: Sheldon often wears different colored shirts with the Lantern logo, but each shirt has a different emotion attached to it in the world of comics.
For example – red is anger, blue is hope and indigo is passion.
Most of the time, Sheldon's behavior in a particular scene is mirrored by the color of his shirt.