A kid gets away with audacious stuff because they've been left in the care of a grandparent who is too senile and addled to notice if, say, they disappear through a Portal Picture to a Magical Land for a few days (probably because they're a victim of the Senior Sleep Cycle). Makes you wonder what in the world prompted their parents to leave them in said grandparent's care in the first place. Examples of Grandparental Obliviousness include: