You won't find anybody more proud of Young Sheldon than Jim Parsons. Parsons, who plays Sheldon Cooper in The Big Bang Theory, serves as executive producer and narrator on Young Sheldon, was clearly moved by the idea of a prequel series about his character.
"It was very moving to me to see this machine take off that's related to all that," he said at the 2017 TCA Summer Press Tour. "I never felt, in the 10 years that we worked on the Big show that we…I can't talk! You don't think you're putting together these kinds of things that will add up to something like [the prequel]."
"It just felt like the greatest idea in the world," executive producer Chuck Lorre said.
A lot of Sheldon Cooper's timeline has been discussed on The Big Bang Theory, like the death of his father, are still canon, but the show will depict how "people change and they grow and develop over the course of many years." Plus, every season isn't necessarily a year.
"Seasons can take place over a couple of months. We have a lot of freedom with the backstory," Lorre said about Sheldon's father, who is played by Lance Barber on the series. "We're going to show there was a great deal more to the man than we discussed over the years on Big Bang."
A lot of talk centered on how similar Parsons was to his character at a young age—" I didn't befuddle my parents, that came much later with my sexuality," Parsons said."—and the similarities between Parsons and Iain Armitage, the Big Little Lies star who has the title role on the prequel.
"I was able to interact with Iain a lot and discuss things that were peculiar to the character," Parsons said about working with Armitage. "Though that I have to tell you it was a very moving experience to me to see something I've put in a decade of my life toward."
The show also stars Zoe Perry as Mary Cooper, the role her mother, Laurie Metcalf, originated on The Big Bang Theory, Annie Potts, Raegan Revord, Montana Jordan.
Perry said she rewatched clips of her mother's work to prepare.
"Genetics do a lot for me. This is my voice," she told the press. "Certain mannerism just come with the territory."
Lorre praised Perry's audition and noted he used to see a five-year-old Perry run around the set of Roseanne when he worked on the show. "When she came into read for the part of Mary, again we were flabbergasted…beyond good luck to have an actress at this caliber," he said.
As for any Big Bang and Young Sheldon crossover, it's been discussed.
"We discussed the possibility that the stories we tell on Young Sheldon could echo on Big Bang Theory," Lorre said. "We're definitely discussing the ripple effect that the shows could have going forward in time."
Young Sheldon premieres Monday, Sept. 25 at 8:30 p.m. on CBS.