Robbie is getting better and better at sitting. He still needs to catch himself fairly frequently but is definitely close to sitting unassisted. He can look around (and up) w/o immediately falling over now.
He is cheating a little at the end, but he'd been sitting w/o leaning for a couple of minutes before I turned the camera on, so I think he can get away with it.
Please excuse my obnoxious narration.