Here is the full list of all 12 Brothers: A Tale of Two Sons achievements worth 1,000 gamerscore.
You sounded a giant horn.
You made someone feel better.
Make a wish.
You practised singing.
You helped the turtles to the sea.
Take a break from adventuring.
Throw someone's ball down a well.
Every family's got one.
Make the bunnies play nice.
Re-unite the two love birds.
Make the inventor dance.
Find the secret.