When people talk to the deciest in a dream have the met the people while they were alive or did they just appear to a random person whom they never knew on earth?

when we speak to a dead person it is often something we wished we said.. or someone we wished were there to advise us.. our dreams are a review of our subconscious... where all our memories are stored.... speaking to dead people is no different from speaking to livng ones in our dreams because those we know are stored in our subconscious