It seems that if you play as the regular kids or the unlocks, the person you visit will always appear as the second part of that pair. I was playing as
and I both went to someone else's Dream and invited another into mine and they both came out as
. The first person I was with only had two Nightmaren in his My Dream and two saplings, so he was probably new at it- most likely a little kid, so I doubt that he had all the Dream Drops. If he played enough to have them all, there would have been more in the My Dream.