And back to the Braganças, when D.Miguel (II) fathered his youngest daughter Infanta D.Maria Adelaide (31.01.1912), his eldest son D.Miguel was already father of a daughter Isabel Nadejda (b.1910) and his 2nd son John would be born the same year (7.09.1912).
Duke Robert of Parma is another case.
His 1st daughter by 1st wife was Pss.Marie Louise (1870-99) married to Ferdinand of Bulgaria.
After her death, duke Roberto still fathered 3 children with his 2nd wife, Louis, Enrichetta and Gaetano, in 1899, 1903 and 1905.
Ferdinand and M.Louise children were older than their 3 uncles.
There was a 35 year gap between M.Louise and Gaetano !
The key in all this, of course, is the ability of men to father children in their 60's and 70's, when they are old enough to be grandfathers and even great-grandfathers.
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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