Miller not only has crawling down like a champ, but he is also pulling up. He is a fast crawler and can pull up pretty quickly as well. He hasn't mastered getting down once he's up though. We have had quite a few falls trying to get down.
Everyone talks about one of their favorite stages is when the baby can sit up on their own but aren't mobile yet because you can put them on a blanket with their toys and they will stay and play. My kids are in that stage for about a week, if that. Once they can sit up on their own, they are off. Miller is causing me to be more tired than Austin (hard to imagine). He is into everything. He giggles when you say no and move him away from whatever it is he shouldn't be playing with. Austin gets frustrated with him because he wants all of Austin's things.
It is a very fun age though. He is still super sweet and just smiles at you when he is on the move.