Of the six young hens, I knew one was responsible for the eggs thus far and had suspected that a second started laying when I got an egg two days in a row.
The second hen had been cackling and carrying on for a day or two (the way the older one does; the younger ones aren't vocal at all), so I thought she might be ready to start producing. I had made a small temporary run and she got out twice yesterday and I still haven't figured out how. As I put her back in she paced back and forth, sounding off and just wasn't happy at all.
As I was making another temporary run yesterday, all six were there with me, checking out the new space, doing the chicken dance while scratching new turf. My suspected new egg-layer suddenly disappeared into the coop and had settled down into a nest she'd made in the shavings. I let her be and just a few minutes later out she came, leaving a beautiful brown egg behind.
Here's an earlier shot of the little lady that's come of age.