In Portugal, surnames should abide to the following rules:
They are choosen among those of one or both parents;
If the parents decide to choose the surname of an ancestor that they don't use themselves, they will have to make proove that such surname runs in tha family.
The order of the surname is completely free (although, in general and opposite to Spain, the father's surname comes after the mother's)
It is admitted a maximum of 4 surnames that can be in sequence or alternated.
Connecting particles can be freely added or eliminated - "and" or "of" 's.
Are parents in Spain not free to choose what surname to continue?
I expect Leonor will use de Borbon y (husband's familyname) for her children and in that order the Borbons would remain on the throne.
In Sweden Daniel became a Bernadotte so Estelle and Oscar are Bernadottes.
The Norwegian royals to the best of my knowledge don't use a surname so Ingrid Alexandra's children won't need one. It will be interesting to see what surname if any will be used for her brother's offspring.
Or they could use the belgian way and become "de España".
(After all, Q.Sofia adopted "de Grecia" and transmitted it to her children.)
Provided Spain would remaine united without a Catalunyaexit
I guess the same could be asked about Sweden, when Estelle will succeed, or Norway with Ingrid's children.
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