Possessives take the same endings as ein: mein Vater, meine Mutter, mein Kind, and meine for every plural. The word itself depends on the owner: mein (my), dein (your), sein (his), ihr (her), unser (our), Ihr (your, formal). So ihr Bruder is "her brother" and sein Bruder "his brother".
Examples
- Mein Vater heißt Thomas.
- My father is called Thomas.
- Meine Schwester wohnt in Wien.
- My sister lives in Vienna.
- Wie heißt Ihr Sohn?
- What is your son called?
The mistake to avoid
A feminine or plural noun needs the -e: meine Eltern, never "mein Eltern".
Where this fits in
Family & people, German A1: Talk about your family, say what people are like and how old they are, and introduce your friends.