When picking outfits I recommend keeping in mind the words “complement” and “coordinate,” rather than “match.” This will create more visual interest, and allow each personality to shine through.
The goal for coordinating a family is to visually break up the colors and shades so that you’re not all wearing the same color on top and bottom. The more I can mix that up, the better. I encourage you to think about planning each outfit with “dominant colors” and “accent colors” in mind. A dominant color is the color that you see the most in an outfit, while an accent has a smaller piece of visual real estate. When you’re planning each family member’s outfit, if you can aim for each person to have a different dominant color, and then tie in and vary the accent colors, it’s going to look great all together.
For example, if you’re wearing a blush dress, soft blue earrings and nude heels (blush being your dominant color), then he could wear a navy coat with a white button-down and gray pants, paired with brown leather shoes and maybe even a blush pocket square (making navy his dominant color). Your daughter could wear a soft blue top with a white tulle skirt (making a soft blue her dominant color) while your son weirs light beige pants and a white button down (making white his dominant color). Now each person has their own dominant color while still incorporating a few touches of the other that will pull all the looks together. This will break up the color visually and highlight each personality.