Onwards and Upwards

Well, we've had a few developmental milestones over the last few days, the result of one being that I have had to use my ingenuity to work out a way of stopping Joseph getting in the base of our fish tank as he's worked out how to open the doors. At the moment it's rigged shut with the strap off an old baby carrier tied round the handles. Joseph finds it fun to play with the strap, but the fish food is safe. He's also worked out how to get into one of the kitchen cupboards which has made me doubly determined to keep him out of that room. The problem with this is that whenever I go in there he always wants to follow. If Andy is home it's fine, he can be the watch warden but when I'm on my own it's harder. If I shut the door behind me then I'm in for trouble as Joseph will crawl up to the door and try and get it open. The door opens outwards onto the living room and if Joseph's close on the other side then I am effectively trapped in the kitchen. This leaves finding a way of keeping him contained in the living room.
He hates being put in the travel cot I sometimes use as a play-pen (also known as "the baby cage"). I can put him in his bumbo but the play tray has to be on or he can escape and I also think he gets a little confused and thinks lunch might be coming early. My other technique (if I was going to be very quick in the kitchen) was to stand him up on his feet and prop him up on a chair as he did enjoy it but hadn't worked out how to get down.
Alas now, he has. It involves sitting down on to his nappy-padded bottom and quickly rolling sideways in the kind of manoeuvre any judo aficionado would be proud.
He does enjoy being up on his feet but until yesterday has always needed help to do so having never elevated himself further than his knees under his own efforts. That's changed now, yesterday afternoon he suddenly got how to pull himself up onto his feet. Twice while I was holding his hands - I wasn't helping in any way - and twice whilst holding onto a chair.
Today he pulled himself up on the side of a chair but didn't get it quite right. Both feet started sliding outwards and he couldn't work out how to stop them. He started whinging and when I looked over he looked like he was practicing for the World Championship Baby Gymnastics. I think he'll be good at the splits.