Kate and the Sliding Door

Where ever we go Kate wants to know what things are.  She has been very curious about the world around her from the beginning of her existence.  A few visits ago to Walmart she noticed the door through which the carts are pushed and then stored.  She wanted to know what it was.  I called it a sliding door.  Now she asks to go see the sliding door and she stands in the entrance and points to the door and repeats over and over again "I see the sliding door".

This is Kate and the sliding door.