News flash from the Animals: we exist in more than one dimension at a time. And - yes, at times we (Animals) can see/sense the energy fingerprints of entities/spirits who drive by to say hello or give us a message. It's not scary - it's normal.  For us at least.

https://www.healthline.com/health-news/we-may-still-be-conscious-after-we-die#Not-dreams-or-hallucinations,-so-whats-happening?