I realised that I never got around to posting any crawling videos. So here is Ivy at 6.5 months having just figured it out and still a little wobbly.
And yesterday at 8 months (and a bit) crawling, standing, cruising. Pretty skillful and pretty fast (despite too-long trousers).
She says "hey" really high-pitched in the video, we often have an exchange of hey's and hi's that lasts ages. I am trying to get this on camera but as soon as I start filming she stops because the camera is too interesting (she is plotting to eat it).