Susan's parents have different hair colors and styles, but their short stature and big heads make them recognizable as a family. Her father sports a bright red shirt and her mother has a white one—a great contrast for coloring.
To bring this picture to life, think of a soft, light blue for the background, then bring in some warmer tones for the clothing. For her dad's shirt, use a bright, hue of scarlet and for her mom's shirt, use a bright white to create a stark contrast. For the hair, use tones of blonde and brown, and their eyes should be shaded in a muted green color. Add in some shadows and lighter highlights to really bring this scene alive.