Ghosts and Ghosts

i'm just as sceptical of ghosts and spirits, but i am still baffled by what we experience. It is one thing to say if i was the only one to witness it, that it would just be my imagination. But my brother saw it at the same time as well. He remembers it too. The only explanation is that there was a window in the parlor, and maybe light was shown through the lace curtains and somehow stopped in the doorway. Maybe humidity, or maybe me and my brother were visited by an extraterrestrial gibson girl. I look forward to hearing yhou guys take a crack at it.maybe you all can think of something i did not consider. You may