You need to complete the following achievements:
Mechanical Brawler
Beast Brawler
Magic Brawler
Undead Brawler
Dragonkin Brawler
Aquatic Brawler
Elemental Brawler
Critter Brawler
Flying Brawler
Humanoid Brawler
You will receive Master Trainer's Tabard.
Here you can buy Family Brawler achievement for EU or US Servers.
You'll get guide for completing Family Brawler achievement
