My niece and nephew get along better than the vast majority of siblings in the three- to six-year-old range. They are best friends and playmates about 90% of the time they're together—and my six-year-old nephew shows incredible patience when his little sister follows him around and emulates and worships him as though she were the Trekkie-under-a-restraining-order to his Leonard Nimoy.
So it's especially amusing—and sometimes alarming—when they act like normal under-10 siblings and start antagonizing each other. Like this morning, when the niece decided to chase her brother around with a pair of scissors.
And like the bad, irresponsible parents, grandparents and uncle we are, we laughed our asses off when the nephew, summoning all his passive-passive powers of persuasion, demanded at the top of his little lungs: Stop! Killing! Meeeeeeee!