I'm no dog expert, but it appears she's labeled you as the "alpha dog," or the head of the pack (don't tell Steve).
You might want to consider obedience school. We didn't for our lab and regret it now. He won't ask anyone but me to take him out (unless I'm not there and he's desperate). And he won't poop except when I take him out.
But for now, have the boys feed her and take her out (even if you're with them). If she recognizes that she'll only get food from them, then she'll change her allegiance.
Like I said, I'm no expert. But you need to address these things while she's young.