Slightly off piste as it's not verbal...
I saw a 2-3 year old this morning escape her Mum and settle down in front of the Primark window. She had yellow sunglasses which she put on, looked in the window, took them off, looked in the window and giggled away to herself. Over and over again. She sat there for a few minutes before her Mum came to find her.
I don't know if she couldn't see her reflection with the sunglasses on, or what it was that she found so amusing, but she had me in fits watching her.