Warning: Time Traveler, beware! You're about to enter a realm of temporal turmoil.
Grandfather Clause Gaffe 3: The Ultimate Time Paradox
In this infamous paradox, a man named Bob travels back in time to 1950s and marries his own grandmother, making his parent his own grandfather. But wait, it gets worse! His parent, now his grandfather, has a child of his own, making Bob's own child his great-grandfather. Mind. Boggled.