Her Wikipedia article is here. She was the daughter of Christina of Lorraine and named after Catherine de Medici, Queen of France. She had several unmarried brothers and sisters as well as sister Claudia and brother Grand Duke Cosimo who married Maria Magdalena of Austria. She married in 1617. Also posted to the Late Farthingale Era - 1590 to 1620 here.
Caterina wears a massive jeweled ornament over the tabs of her bodice in lieu of a girdle.
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