Since the parent and the child were the only ones home at the time, it's a good bet the parent knows the culprit.
When confronting the little rascal, you'll see the child's mind going to work by the way they move their facial muscles and then blurt out that some made up, invisible friend was the one who wrote on the walls.
Coming from a child, who doesn't know any better, it's almost cute and laughable.
But what's not cute or funny is when the USA and its trained lap dog, Britain, shout "aL Qaeda" anytime they get caught in some murderous activity, like the British police beating a man to death who's only crime was walking home close to a peaceful demonstration.
Or the US Department of War, always making grim announcements about the number of "al Qaeda" fighters killed in the most recent Predator drone missile strike, when the dead are largely Pakistani civilians. Or those Iraqi IED's, that always seem to blow up whenever there's talk about the US pulling troops out of that destroyed nation... Again, blame it on "al Qaeda."
And blaming the horrific 9/11 attacks on some Muslim, needing dialysis frequently, who was living in a cave 12,000 miles away, when we all know the real 9/11 perps were closer, much closer to home. Some are hiding behind Secret Service agents, others, behind a weirdly shaped six-pointed star, still screaming far and wide that "al Qaeda" was responsible for 9/11.
That's when the cry of "Mommy, al Qaeda did it" doesn't sound so funny.