First, you don’t have to, it’s a useful convention.
Since the middle ages, the west has used a seven note scale with five whole steps and two half steps. This gives one scale, c major, with seven natural (neither flat nor sharp) notes.
As an aside, I believe there are six note scales.
Uncle Iroh
I know he’s a genocidal war criminal, but he lost his son and traveled a long path of tea and paisho eventually cherishing and mentoring his nephew.
Uncle Ruckus
He’s a simple man, tryin’ to make his way in the world. Life’s dealt him a tough hand, but he played it the best he could. He worked hard, respected the values he was raised with, and tries to bring a bit of order to this chaotic world. He ma be rough around the edges and may not make words so good, but he believes in tough love and speaking his mind.