We should have guessed it. She spends ten hours a day at a French day care center. She spends weekends and a few hours a night on weekdays with us. We were kinda worried she wasn't learning English that fast. But we visited our downstairs neighbors, who had guests, and Jesse got along just fine with their francophone daughters. Turns out she hasn't been saying "I got?," she's been saying "encore?"
Which is a little disconcerting, but a relief at the same time (she's much further along than we'd thought, only in French), and come to think of it, kinda cool.
Now how do I get the Teletubbies song out of my head?