The farm is not haunted. But don't tell that to Billy.
The oil fired steam boiler which keeps the farm house warm and cozy in the winter is rather old, a conversion from coal fired which in turn was a conversion from dried dinosaur gauno fired (from back when live dinosaurs were plentiful). So we're replacing it with a new natural gas fired boiler.
Being a steam system, this work means our plumbing has been opened up, and a few air bubbles have gotten in the system. This leads to water hammers and related vibration in the pipes.
One flush of the toilet and the resulting screech as the tank filled and shuts off left Billy shaken for minutes. He looked so troubled that I did an exorcism on the house, running the bathtub to flush the remaining air out.
We hope Billy won't need counseling.