couple of my baby buddies have commented on it - things like the older child trying to offer toys and covering the baby's face. nothing major happened, but it made me think of the importance of making sure you can keep them seperated while you're not there to supervise (and as good as you are - you'll have to leave them - damn that bladder lol)

i would probably think play pen more so than portacot - i think it would work better and A would be less likely to try and drag it over...