Family members [that are not first degree relatives] will typically have titles based on to which parent they are related.
Grandfather
Ông (generic)*
Ông nội (paternal grandfather)
Ông ngoại (maternal grandfather)
Ông cụ (great grandfather)
Ông cụ nội (paternal great grandfather)
Ông cụ ngoại (maternal great grandfather)
Grandmother
Bà (generic)*
Bà nội (paternal grandmother)
Bà ngoại (maternal grandmother)
Bà cụ (great grandmother)
Bà cụ nội (paternal great grandmother)
Bà cụ ngoại (maternal great grandmother)
Dad, Father
Cha
Bố (Northern dialect)
Ba (Southern and Central dialect)
Mom, Mother
Má (Southern dialect)
Mẹ (Northern dialect)
Children
Con cái
Daughter
Con gái
Son
Con trai
Brother
Anh (your elder brother)
Em trai (your younger brother)
Em út (your youngest sibling)
Sister
Chị (your elder sister)
Em gái (your younger sister)
Em út (your youngest sibling)
Uncle
Ông (your great-uncle)*
Chú (your father's younger brother)
Bác (your father's or mother's older brother)
Cậu (your mother's brother)
Dượng (your dì's husband)
Aunt
Cô (your dad's sister)
Bác (your father's) however for your mother's older sister or brother only Northern Vietnamese in recent 100 years)
Bà (your great-aunt)*
Dì (your mother's younger sister)
Thím (your chú's wife)
Mợ (your cậu's wife)
*Ông and Bà are generic terms for an older man or woman, respectively, typically with a two-generation gap from yourself. Using your grandparents as a baseline, any person that falls within the same generation are typically referred to as Ông and Bà (e.g., your grandparents' siblings and first cousins). For great-uncles and great-aunts, the Ông and Bà are followed by the title of what your parents call them (Example: Ông Cậu would be your mom or dad's Cậu (mom or dad's mother's blood-related brother, or your grandmother's brother for simplicity).
If the title has more than one word, the last word is a description of the base noun.
