Second Daughter has a tooth! It's just a tiny white speck on her bottom gum. She was quite displeased when I tried to reach in and feel it, so I'm not quite sure, but it's possible that it technically hasn't broken the skin yet.
I tried to zoom in on it for you.
In other news, or non-news as the case may be, she's not really rolling over. Twice she accidentally rolled from her tummy to her back, but nothing since. I'm not really worried, but I have started being a little more diligent about tummy time, which she doesn't much enjoy. I've also started trying to place myself just enough behind her to encourage her to twist to see me while she's lying on her stomach. Other suggestions are welcome.