I had meant to post about this a few days ago, but never got around to it. And since I just posted about how quiet the birds are in the morning, I might as well follow up with this as it has to do with noise.
It turns out, Léa has started to give any noise-making flock member a stern "Hey!" when she thinks they are too loud. The Boy was the first to report about it, but I did hear her do it twice through the birdroom door - quite funny!