Her Wikipedia article is here.
From Wikimedia; image lightened to bring out details and approximately doubled in size.
Sophie Friederike is dressed warmly with a bonnet merging with the neckline of her dress and a cape or shawl. Warm sleeves and a red scarf complete her warm dress.
Keywords: Waldmüller, Sophie Friederike of Saxe-Coburg-Gotha, Sophia of Mensdorff-Pouilly, Countess of Mensdorff-Pouilly, Princess of Saxe-Coburg Gotha, Sophia, Mensdorff-Pouilly family, Wettin family, Princess, Countess, German, hurluberlu coiffure, bonnet, bows, shawl, lace, scarf, long full sleeves, cuffs