"Yep," Penny said brightly, bouncing on her heels. "Let me just text Penelope first and let her know where I'm going."
Because the woman had no problems with Penny going where she wanted, when she wanted -- within reason, obviously -- but that didn't mean Penny could just wander off randomly. But Penny would've let the woman know even if she didn't actually have to. She was a responsible kid, for one thing. For another, Penelope was an awesome guardian.
And Penny had been raised to respect authority figures -- even if the lesson she'd ended up learning was "as long as they deserve it to begin with."