Each family has its own special trade, depending on how close to someone in your family you are they may give you discount items from that profession.
Below are a list of all the family trades.
Blacksmith - Forges weapons and armour.
Tailor - Crafts accessories.
Farmer - Grows wheat from wheat seeds.
Rancher - Raises cattle for meat.
Miller - Mills wheat into flour.
Fisherman - Catches fish.
Merchant - Offers items for sale.
Alchemist - Creates designs for weapons and armour.