Dean has always loved listening and dancing to music, but he's never shown interest in singing with me until this week. For some reason he really took to the "eieio" in Old MacDonald. It's not always discernible to untrained ears, but I can tell what he's "singing". Sometimes he'll insert his eieio into other songs as well now. Also, he's discovered head phones and think they're great. He'll (with my help) plug my headphones into my computer speakers, put them up to his ears, lay down on the floor, and shake his head and/or body to the music. He also loves clapping rhythms (not necessarily on rhythm) with me during piano lessons.
I tried to catch Old Mac today on video, but it's so hard to get a good video when he's so enthralled with the player.