Does drinking protein shakes at age 12 stunt growth?

I don't believe that protein shakes will stunt your growth. There are different types of protein shakes such as whey, casein, soy, and recently there is some buzz about hemp protein.

Active people who are still growing should get most if not all of their nutrients from wholesome foods and not from supplements. For protein you should be having beef, chicken, and fish among other kinds of protein including healthy carbs and fats.

It's usually only when you are competing at an elite level when you need supplements that can give you that extra edge.