Your brother's daughter is your niece. You are her aunt (if you are a woman) or her uncle (if you are a man).
your 5th cousin
She is his dad's brothers daughter. She is Brice's cousin.
Are you asking what you call your brothers daughter? Well if you are your brothers daughter is called your niece.
Poseidon and Zeus are brothers. Athena is Zeus' daughter. Therefore, Athena is Poseidon's niece.
Daughter
Your brother's daughter would be your niece.
Your brothers ( or sisters ) daughter is your ( niece )
Your brother's daughter is your niece..and you are her AUNT.
3rd cousin I think:-)
The Judds, Naomi and Wynonna, are mother and daughter. Loretta Lynn and Crystal Gayle are sisters. The Gatlin Brothers are brothers. Johnny Cash was Rosanne Cash's father. The Wilkinsons are a father, his daughter, and his son. Hank Williams and Hank Williams, Jr. were father and son.
Niece
A niece