All four of the locations were from rooms that were interconnected in the home, and the orb pattern was different in each.
These different numbers and patterns of orbs would indicate that the anomalies were likely not caused by dust or smudges on the camera lens.
This home dates from 1891, and certainly has a long history as does the town itself. Although a 'friendly' and quiet town, Grafton is home to many occult, masonic types of organizations.
These organizations - from outright Masonry and Eastern Star to Rotary and Lions Clubs - are quite well known to be a veiled form of Lucifer worship.
Not too surprising, then, that a good many of the homes there - and especially the older ones - would have spiritual activity of the malevolent kind.