Take, for instance, a look at Crown Prince Rupprecht of Bavaria, who fathered his youngest child (Princess Sophie, by his second wife, Princess Antonia of Luxembourg) at the age of 66. By then, his son Albrecht (by his first wife, Duchess Marie Gabrielle in Bavaria) was already 30 years old, and a married father of three. As that would have been in the year 1935, this would mean that Princess Marie Gabrielle of Bavaria (his only living daughter) and Duke Franz (current head of the House of Wittelsbach) have an aunt younger than themselves.
Of course, she is only a half-aunt; but she nevertheless belongs to an older generation. I've often wondered what they call her. "Aunt Sophie"? ...
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