This addon will help you to track Stagger duration and stacks applied by Stone Giant ability.

It also tells if the next cast of Stone Giant is the initial cast (AoE) or a projectile by changing the icon's color (AoE is grayed out).

Normally the icon appears in combat if you are a DK and have Stone Giant slotted, but you can also display and move it by typing /StaggerTracker in chat.