kuseta........I do believe in ghosts. I've not experienced any "human" ghosts, but we do have cat ghosts at our house of those that have left our family. I can feel them jump on my bed or lay against me at night and nothing will actually be there, or will feel them brush against me when I'm standing. I find it rather comforting.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I also 'know ' that my pets have come back to visit. The same way that you do. I have felt the cAts jump on the bed in the same way that they did in life.
So now when a pet has got to move on and I have the precious time to comfort them first, I always invite them to come back and visit any time that they want to. So far all but one has come back to say 'hi'. We are still waiting for the last one that left to return for a visit or a last goodbye.
This has become a treasured tradition in our family.