Actually they do. It's called an Arms Reach Co-sleeper: http://www.armsreach.com/ We have the regular sized one, but they also make mini's. The regular sized ones are the same size as a standard pack n play, the co-sleeper doubles as a bassinet and pack n play as well as a co-sleeper.
To attach it you have belts that slide between your mattress and box springs and attach to the co-sleeper. We love ours, even though the majority of the time Elah ends up in bed with us! :)
at 1:53 AM on Jul. 13, 2011