Potty Learning and Funny Things My Son Says...

So, L is 19 months old, and today she had only one 'oops' in her diaper, all of her own volition. I have not initiated toilet training at all with her. Last night, I was awakened to her screaming (and signing with both hands) "POTTY!!! POTTY!!!" at 2 am. So, we went. Today at preschool, she told her teachers she needed to go. Twice. I really don't know what to make of this at all. She's been going potty a lot over the past month or so, but I kind of figured it was a phase. I'm thinking that she's actually training herself at this point. M didn't potty learn until he was 3.5 years old, and that was only because my MIL went cold turkey on him, while he was staying there for a few days. Trust me, I'd been trying for about a year.

And, for the latest installment of what my son said today at preschool:
One of his friends threw a frisbee really hard over the fence of the playground. A college kid picked it up, planning to give it back. M starts yelling at him "Hey! That's our frisbee. You can't take it. That's not nice!" The kid is obviously flustered as he hands the frisbee to M's teacher, who explains what was going on to M. M replies "I thought he was going to take it and run!"
Take it and run? Where the heck does this stuff come from?