A lot of non-show cats have ghost stripes, and a lot of kittens start out with them but lose them along the way. The tabby gene in cats is pretty powerful and it affects how the hairs reflect light as well as just arranging the pigment. Reds are the worst, because the non-striping doesn’t affect red pigment, but even in black and the variations thereof, the stripes will often manage to show through. I’ve even seen some white cats that had stripes when the light was at the right angle.
Those are beautiful – but I bet they’ll make life interesting for you! Enjoy.
(And do post a pic of Gandalf once he grows his beard in! 😀 )