dream

i’ve recently had an old co worker/friend pass away and i’ve been having dreams about him. in the dreams he’s still alive but i know he’s already passed away technically and i start crying and tell him i miss him. he tells me he misses me too and that everything will end up being ok (i’ve been having a hard time with things in life recently). is it true that when someone from the dead comes into your dream, it’s actually a sign of them from the after life sending you a message? sorry this is all over the place but i’m just curious about it