A dream of ghosts and languages

Strange dream last night. I was talking with an unidentifiable friend and with my paternal grandfather when my paternal grandmother passed by, said something and left. It all looked normal at first but then I remembered that she had been dead for a long time. I started to discuss how that was possible, suggesting that it was probably a collective hallucination, when my unidentifiable friend switched to English. I realised it was to protect my grandfather, who probably had never realised that my granny was dead (in reality he's dead too, but in the dream either this wasn't the case or it was irrelevant) and who couldn't understand that language. My grandad started to get closer and closer so I said to my friend that what we were doing was actually cruel: he had serious hearing problems and now we were giving him the impression that he had lost the ability to understand us altogether. And then I woke up