Complex sentence: Some fans theorize it's Unicorn blood, which is likewise silvery in color; however, given how all ghosts of Hogwarts have a silvery hue this may be a coincidence.
Split into simpler sentences: Some fans theorize it's Unicorn blood, which is likewise silvery in color. However, given how all ghosts of Hogwarts have a silvery hue, this may be a coincidence.