I had a RoadTrek that did that. The 2 front seats rotated about 180 degrees and the 2 back seats rotated and laid flat to form 2 single beds. Problem is that the seats are just like any other bucket seats, so they aren't totally flat when laid out in bed format. They're also not any wider than your rear end. You can't even sleep with your arms at your sides. They're also 2 or 3 feet off the floor, so if your child tosses in their sleep they may wake up in mid-air. The rear dinette has problems as well. If you're over 5 feet tall, you have to sleep diagonally if you want to stretch out.
Roadtrek sells their product as everything doing double duty, but the compromises aren't worth it. Your toilet is also your closet. The shower is also your kitchen. There's a plastic insert to turn your kitchen sink into a bathroom sink.
Other folks like them, I didn't like mine. Check one out thoroughly if you're thinking about buying. Your opinion may differ.
Retired and visiting as much of this beautiful country as I can.