I looked a little farther under the bed and found this: another happily
sleeping boy...under his brothers bed.
While I tried to gently coax Oliver out from under the bed without startling him so that he jumps up and bangs his head, I woke Mason up and sent him out to the bathroom. I got Oliver all tucked into his bed and waited for Mason to come back in to go back to bed. After a few minutes, I got suspicious of how long it was taking him to go to the bathroom. I went to get him and I found this: