Inner Child

This week we were house sitting my wife's parents home. I was snooping around and found some boxes that had things from her childhood. So, I started going through the boxes with her. I found something that I use to have when I was little. Something pretty simple that I used to enjoy playing with. I told my wife I was going to take it back to our home.
Well, tonight I was sitting around and looked over and saw this thing. I said to my wife, "we have stairs." We both lit up with anticipation and excitement. We took it to the stairs and let out our little "inner child". Nothing but smiles. What was it? It's the plastic rainbow Slinky.