They fight... oh how they fight. The older knows how to push the younger's buttons. The younger knows precisely how to shriek loud enough to get the older into trouble.
They battle to see who can scream the loudest or sit on the chair first or walk across the floor the fastest. They always want to use the same cup or spoon or napkin or basket at the same time.
The older gets frustrated when the younger just. won't. leave. her. alone.
The younger gets angry when the oldest doesn't want to play.
They couldn't be more different.
But they wouldn't know what to do without each other. They're in cahoots. And they couldn't love each other more.