I did a bit more research and was able to locate the location of the light switch downstairs that had the droplets of blood: the hallway near the living room.
Bonassi Deposition:
Riccardo Lucciano Depostion
In the police downstairs video (at 8:07 both are visible), there are two light switches in the living room/hall area. One by the front door with a chair next to it and the other between the green bureau and another door. Both would provide a higher position from which blood could spatter from a cat shaking its head. The one by the green bureau would be at almost the same height as a cat.
Something I just noticed: the window in the downstairs bathroom is OPEN. It's dark but look carefully at the chrome latch handle to the right of the white shutter. The window is open at a 45 degree angle making it appear like it's the casement around the window at first. The video goes by it very quickly, but when I froze the screen and enlarged it. it was definitely an open window. Since the window has a bars, the was no safety reason not to leave it open. So that is how the cat got in and out. Also notice there is blood spatter on the bathroom wall (about 8:53 in the video).
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