Child1: (checking to see if sibling is awake or not) "I'm Having The Last Word"
Child2: "no you're not..."
5 minutes later...
Child2: "I am".
Child1: "No you're not, I am".
some time later...
Child2 calls name of Child1.
Child1: "what?"
Child2: "I'm Having The Last Word".
... continues until only one child remains awake and whispers, "I WIN!".

The object of the game is to "have the final say" before falling asleep. The Winner is often disputed the following day as nobody else was awake to verify his or her claim.

In brief: A game as silly (empty) as playing Tic Tac Toe (UK: Noughts and Crosses).
Some say the game was a method introduced by parents to get their offspring to go to sleep but this claim itself is also disputed; My younger brother and me invented it and IHTLW :P so there! Word.

Bro since I got dirtpilled on Tuesday I have made sooo many worm friends and made them soo many little houses to get married in. Me? Lonely? No you’re the lonely one u lawn owning freak