Storing Messages and making Declarations in Code

I'm working on a game in which in the current build the player clicks on an object, and a message pops up that says "You clicked on (name)", and then disappears. What I want it to do is hold onto that message, and then be able to click on a second object. A second message would then pop up underneath the first, also saying "You clicked on (name)".

However, I want it so that the engine only holds on to two objects at a time. So that when you click on a third object, the first object's message is deleted, and the new message for the third object comes up. I'm not sure how to do this.