"The Big Bang Theory" spin-off "Young Sheldon" will be an origin story of Sheldon Cooper (Jim Parsons) of the flagship series. However, the young Sheldon (Iain Armitage) won't be as overbearing as he is as an adult. Also, Armitage gets acting tips from Parsons.

"Young Sheldon" co-creator Steven Molaro told reporters at the Television Critics Association summer press tour last week, "We have the opportunity to look at Sheldon as an adult and think about the origins of how he came to be."

Aspects of how the adult Sheldon came to be, like his love for comics and how he likes to go to church with his mom even though he doesn't share her views, will be explored in the spin-off. Viewers will also get to see how the people in his youth influenced him to become the man that he is today.

Co-creator Chuck Lorre also shared that the young Sheldon will not be annoying like his older self and will not be a brat.

He explained, "He's not yet become cynical and overly controlling. He has his idiosyncrasies but he's much more vulnerable and naive when we enter the story in 1989."

The adult Cooper comes across as sarcastic and likes to criticize his friends. However, audiences forgive this about him because of his quirky nature, which is what is funny about him.

In related news, Armitage recently shared with TV Guide how Parsons' advice has been helping him get into the role of the young Sheldon. He said, "Advice can be 'maybe we could say this line differently' to 'let's play this scene a whole different emotion.'"

The young actor also said that he and his character enjoy different pursuits. Armitage likes theater, magic, taekwondo and stuffed animals while young Sheldon likes Math and Science.

"Young Sheldon" will premiere on Monday, Sept. 25 at 8:30 p.m. EDT on CBS.