You'll want to look for a dress that blends with the bride's chosen colors. Most moms use the bridesmaids dresses as a palette. If their mother of the bride dresses knee length are green, you shouldn't choose a pink dress. A different shade of green or even a dress in a complementary shade of blue would be a better choice. You want to avoid white, ivory, black, red, anything too bright (like an electric-blue gown), and anything too overdone.
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