What seems to be the difficulty, son of my best beloved sister?

No son of Constantine's sister would have been referred to in this manner.

A son of his mother's sister, this man, then, was his own cousin.

The micoor chiefis usually the eldest son of the chief's sister, but in these days things sometimes change.

That is so the son of my sister and your father's brother.

We are friends of the son of your sister, Fauzia.

I need not tell you that the son of my sister is welcome among my knights.

I am the eldest son of your father's youngest sister.

Thus they took their leave, and Edger at last turned his attention to the son of his sister's sister.

They are the sons of my sister who married an American.