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Sophie was born a very large baby, but her fragile health was undermined by tuberculosis. She died in Versailles after suffering five or six days of convulsions. She was only eleven months old.
Her death was a cause for much sorrow on the part of her parents. When Marie Antoinette's foster-brother, Joseph Weber, attempted to console her with the fact that given Sophie's tender age Marie Antoinette must not have grown overly attached to her, the bereaved mother is supposed to have said, "Don't forget that she would have been my friend." This was a reference to her words after the birth of Sophie's older sister in 1778.
The Royal Family of France, 1787Queen Marie Antoinette with her children, 1787 at Versailles; (L-R); Marie Thérèse, known as Madame Royale at court; the Queen with the Duke of Normandy on her lap; the Dauphin is on the right pointing into an empty cradle; the cradle used to show Madame Sophie; she died later in the year and had to be painted out; by Élisabeth-Louise Vigée-Le Brun; the Fleur-de-lis of France and the Bourbons can be seen behind on the cabinet