If the brother or sister in question is the child of the previous monarch, they would usually be called a prince or princess. However, in some countries, such as England, a king may grant his close relatives, such as siblings or extra children, noble titles, as duke, duchess, count, countess, etc. at which point they would be called by that title, but it varies from country to country
The princess is any female relative of the king or queen; for example princess Margaret was Queen Elizabeth's sister.
you call her your daughter's husband's sister
Ankhesenamun was King Tutanhamun's sister and wife.
You don't call your brother's sister your aunt. Your brother's sister is your sister, or you. Your aunt is the sister of your mother or father.
You would call your mother's sister an aunt.
You would call your sister's daughter your niece.
Your child would call your sister her aunt.Your sister would call your child her niece or nephew depending on gender.Your sister's children would call your child their cousin.
King Tut's half- sister and wife was named Ankhesenamun.
sister = sahodari older sister = chechi younger sister = anujathi
sister in law
The relationship of the sibling of your sister-in-law or brother-in-law to you does not have a name in English. You could call them your brother- or sister-in-law if you want, or you can call them the brother or sister of your brother- or sister-in-law.
sister in law