Happened to me and my mother.
Our family came to live in an old apartment allotted by the government, we were oblivious to the fact that a person had died in there and people who had occupied the place before us have had bad experiences. My health started to deteriorate for unknown reasons, I started seeing some of my dead relatives in my dreams and used to wake up exactly at the same time around 2:45 AM in morning.
Sometimes I oversaw a manly figure strolling around, but ignored assuming it to be my father. One night, both me and my mother woke up and both saw the man in exactly same profile and at same time.
My mother raised an alarm thinking that somebody had broken into our house. But then the neighbours started telling stories and we moved out on the very next day, shifted to a new residence.
a friend, child of a single parent, once in childhood had suddenly fell under a spell of severe fever. no variety or amount of medicines worked to alleviate it (mother's an allopathic doc who resigned from a very senior position under the MP Govt.). he used to have an old Daai Maa then. she then applied one famous remedy, of burning red chillies, and spreading its smoke around the patient/victim and the surroundings. he tells that both of them got burning red watery eyes and were coughing, but he didn't feel a thing during the whole episode. his fever then started subsiding to none after it was over.
anyway, I had written the post that you quoted, only jocularly. that was also a sarcastic remark to those who give/gave that blanket-explanation for the effects witnessed by more than 25 journalists and investigators, from one of the investigators of the famous Doris Bither case of the 70s (inspiration behind 'the entity' >> 'hawa').
coming to sightings of 'dead' relatives/parents, people from familial relations, when they leave their bodies, they do come back for either a short visit to look over, or keep a watch over for a temporary amount of time, or would persistently keep trying to contact you in case there's some urgent left-over work (I've learnt that they have this 'concession' before crossing over and moving on fully towards the next cycle/phase). mostly the communication would be (preferred) during the subject's sleep, and at the TWILIGHT stage (ie, when the subject is aware but not awake, about to go in deep sleep; its 2 times - after lying down, and in early morning/before dawn when the body is ready to be awake. the former state is 'better', a point at which visions, revelations, sublime experiences, etc. happen, and is the preferred state also for practicing astral projection).
one experience from my family - the eldest brother of my maternal grandfather had left the mortal world quite some time back. the 3rd eldest brother of him, he stays at Pune, with son and bahu settled in London (this was a couple of years back). now this grandpa, named Bhadranath, does regular Yogaabhyaas and meditation in the morning. one fine day, during his meditation, he had a vision, wherein the eldest grandpa came and said - "arey Bhadra! main waapas aa raha hoon." Bhadra nana, having gotten the hint, rose up, and said to nani to call the son at London in sometime. this, because his wife was expecting delivery. she did deliver a son that day.
now those who have studied and observed in their life the Karma-siddhaant and how it manifests in life esp. in reincarnation, would know that deceased in a family usually take birth in the same family for exhaustion of their Karmic rnanubandhan.
experience of a friend - his grandfather had expired. he had been to his paternal home, and the next night he slept on his bed. the table and chair of his grandpa were on the right side of him near the door, facing the wall. it happened that in the morning at about 5 his eyes opened (as happens usually, like I wrote, the phase when the body/mind is coming out of sleep), and distinctly saw his grandpa pulling the chair and sitting staring at him. he dismissed it and went back to sleep like we all do. woke up again and found that the chair was indeed in the same position as he saw it at 5. call it what you may.
another experience - a friend used to stay at his deceased grandma's home for some time. one late night he slept off after watching pron. in the middle of the night got woken up getting one tight slap! he used to stay alone there.
same friend - used to go for early morning walks, esp. during winters. place was Juhu/nearby. one day he recounted how that day while walking the path he though he saw a person standing near a pole (there was no other human in sight in those wee hours), thought nothing of it, saw down for a second, again looked in the same direction, there was nobody there. while telling this he kept dismissing this laughingly saying that he may be feeling groggy and his sight may have been hazy. anyway, it ended there.
fast forward a few days, a mutual friend staying in the same area and who used to go jogging early morning, said that he was going in the direction of a dead-end which's adjacent to Juhu graveyard. on the way he spotted a lady in burqa. he looked at her. however, she seemed to be intently staring at void in front of her, mindless of this friend and him looking at her. what more he felt odd about was that she didn't have the up-down motion of body of a human's gait. it was as if she was gliding. anyway the dead-end wall was near, and as soon as he reached it and turned around, there was no sign of the lady, and the path was a straight long one.
in my view, if he indeed spotted an apparition (which he did seemed to me), that gliding motion would most probably have been because when that lady had expired, the ground level would've been lower, but over time with pavement work, it rose. I say that from the observation of an engineer who had been posted for work in the premises of the very famous Borley Rectory in the 70s (one of the most densely haunted sites in the world, later razed down to the ground due to many disturbing sightings & poltergeist like annoyances.