A "family" of color is just a slice of the wheel.
Every color has a hue — its angle (0–360°) on the color wheel. Reds sit near 0°, greens around 120°, blues around 220°. Pin the hue to a narrow band and everything inside it reads as the same family: all blues, all greens.
Pick a family below. colorFamily("blue", n) walks the hue evenly
across that band (and arcs the lightness up through the middle) to hand you an
ordered range of that color — the grown-up version of "give me a random blue."