Thanks for the update

. You should definitely do research on the house and see if you can find anything! Maybe you can dig up the original floor-plans and see if there was something different about the room that your dog is digging at the corner in.
What do the animals say to your son?
In reference to orbs; most people believe orbs are just airborne dust particles, bugs, etc. I usually believe this to be true. When looking at your photos, trail-lines or brighter orbs usually suggest something paranormal. Multiple orbs usually mean dust particles.
I look forward to seeing if you capture anything on photo

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