i just had one recently, not a within exactly, but where one of the things that happened was i was explaining to someone in it, about something that had happened in another previous one! (and in the previous one i was explaining about, one of my neighbors was breeding and raising reptilian 'cows'. basically kind of like large dino's, that were mostly harmless other then their size, and pretty much cowlike in their behavior)
I knew that I was dreaming and as I was talking to a woman in the dream, I told her "I had a dream about you." Seemed kind of odd when I woke and thought about it.
Yes these are called DOUBLE DREAMS and I have had them a few times...... I have heard it means someone is becoming spiritually aware of things..........