The sister of a King don't have a title apart the one she is born with or got through marriage. Being born sister to a Crownprince she is most likely Princess but she can get another title through marriage.
There is no standard specific title for the niece or nephew of a king, the way the son of a king is a prince and the daughter as princess.
royalty
morgan la fey
morgan la fey
in the tv series Merlin yes he does
she was callled the kings bellowed sister because she treated him like a brother
Yes she has a brother named johnny king and a sister named Wanda king I think she has some other siblings not that I know of, but I got this information of this show called "Unsung"
Prudence King's middle name in 'Love Lessons' is Elizabeth.
A Queen's sister is called a Princess. Even the queen was a princess prior to becoming Queen of XXXX. The Princesses and Princes are the offspring of the King or Queen.
Martin Luther king had a gorgeous older sister called Willie Christin king and a younger brother called Alfred Daniel Williams king.
Ankhesenamun was King Tutanhamun's sister and wife.
King Tut's half- sister and wife was named Ankhesenamun.
If you mean Bernice or Berenice, she was his sister and being called the queen maybe his wife as well.
Your sister's husband is called your brother- in-law.