D1 has been growing too fast in too many ways to note them all, but here are a few:
Self-endangerment: She has now gained the strength and mobility to entrap herself in things, without having the strength and mobility to escape. We are going to have to put the baby seat away, after I discovered her hanging herself over the toy bar. She can also tug on her arch of toys that hangs over her playmat until it falls over on top of her; fortunately it doesn't hurt.
Sock removal: She has recently discovered that she has toes. She has not succeeded in removing her socks by this means yet, but she practices diligently.
Social coughing: For a while we thought she had an allergy, but we have finally come to the conclusion that she has figured out how to cough on purpose and is trying it out, as she tries out every sound, to find out its significance in the English language. She also makes interesting clicking noises which, alas, will not help her since we're not !Kung tribesmen.
Sitting up: She can sit on my lap without falling over for . . . well, five seconds at least. Maybe ten. It's a start.