It really is quite common for a newly passed away person to stop for a final visit with a loved one, or even just a casual acquaintance. Whether it is a parting kiss or a message saying that all is okay or a peek at someone they wanted to see in real life and had not, is a query. But common it is and I do not consider this a haunting or a sign that a ghost is coming to stay in your house.
Also it sometimes happens that a person passes away and does not realize it. As in Ghosts of Bordentown Gay states “Mom, it’s the strangest thing. I wake up and hear sounds of someone brushing their teeth.” The former, elderly owner of the house took to the habit of brushing her teeth in bed after she broke her hip. Apparently she didn’t realize at first, that she passed away. This faded after a time.
The same situation occurs in “Spirit Doesn’t Know She Is Dead” Heidi’s Story coming up in Ghostly Spirits in Warren County, NC & Beyond. Apparently some take a little longer to realize they aren’t on the earth plane anymore.