Or if the Grandpa-is-a-ghost theory is correct, it could be long-term exposure to him causing Isabel to become a spectral with the same energy color.
Plus then you get to bust out all the "he was so much easier to deal with when he was alive" references.
Man I am so here for all the kids learning to get along because the magic of ghosts FRIENDSHIP oh my god this comic warms me to my very soul.
My favorite part is how Max is so O_O his eyes are visible in his shadow. This comic is the greatest.
I cannot get over the sheer, beautiful absurdity that a dry twig appeared in the middle of the bare hallway just for Ed to step on it. It makes me want to quote Mark Twain.
SCREEEEEEECH Spoiler: the update i know you're gay, but try to keep your composure i know you're gay, but try to keep your composure I KNOW YOU'RE GAY, BUT TRY TO KEEP YOUR COMPOSURE I THINK THESE EXACT WORDS HAVE BEEN SAID TO ME THIS IS WHAT IT FEELS LIKE TO BE REPRESENTED