I actually have stuff from a recent episode to do the next prompt about! Yays!
Always stand up for and support her.
When Leonard found out that Sheldon and Amy were coming to see Penny in A Streetcar Named Desire, he was glad that some of their friends would be there for her as well as her boyfriend. He knew that she'd been hoping the opportunity would arise to invite some of their friends, since other people in the acting class would have a half dozen people there.
"Of course I'm glad you're there," she had told him when he asked her, teasingly, if she wanted Shamy to come because he wasn't enough. "I wouldn't be able to get through it if you weren't."
"You'd be fine," he reassured her. "You've done acting jobs without me before."
"I know," she said, "but this is me among people I work with. That's so much more pressure than standing in a room with people you don't really know. Knowing you're there, it'll calm me down. But it will be nice to have more than one person, you know, because most of the other people will."
"They'll be there. And I'll make sure Sheldon's paying attention," Leonard said, smiling.
"That'll be tricky," Penny said. "You know he hides his toys as well as I hide from the landlord."
"If Sheldon's going to your play, I'm going to make sure that he is watching you and your peers every second," Leonard said. "It will be seen to personally. Doesn't matter how many items he shoves in his pants, he will not be leaving the apartment with them. Not when you need us."
Penny wrinkled her nose. "He hides things in his pants? How in the world do you know that?"
Leonard put an arm around her and kissed her cheek. "You don't want to look under that rock."