Careful, they can be different configuration on different lines. On Princess, if you book a cabin for 4 you cannot have the primary beds configured together. Also, on NCL some ships have cabins for 4 that are true bunk bed configurations. Again, that means Mom & Dad cannot share one big bed themselves. Ask...if the booking agent doesn't know on the ship you're considering (common, also common for them to answer wrong) have them check. It's easy to give the standard answer that applies to the majority of ships. I've made the mistake in the past myself. One unhappy client and you check each time forever more.