My ds is 5 months and we co-sleep with a bedside cot, although normally halfway through the night I put him next to me on the actual bed (or at the moment with the teething on top of me, but that's another story).
Anyway, at 5 months he is now starting to be very mobile and will soon be crawling so I am a bit worried about nap times and the early part of the night when I am not in bed with him yet, as I don't want him to be crawling over to the bed and falling.
My bedside cot (babybay) does have a barrier for the bed side, but it's a PITA since you need a screwdriver to put in on and take it off. So what do other people do once your dcs can crawl or are about to? Do you have a separate cot for naps and when you are not there?
I wish I had thought about this when I bought the cot and gone for one with a more user friendly barrier....