How do I add one instance variable to all the sprites in a container?

Is it possible to add one instance variable to every sprite in a container as if they act as one sprite? (eg. add a string variable to 3 different sprites in a container, and have them all respond to the code.)

With a container when you pick one of the objects in the container it picks the others too so you would only need one variable on one of the objects for it to act as one sprite as you described.