Lunch bags become purses.
Brain development occurs. Example: Today I said, "Nellianne, it's night night time. Let's get ready for a nap." She walked across the room, flipped open the flap on her num-num pocket, pulled out a num, popped it in her mouth, snatched her blankie, walked back over to me and collapsed in my lap. I think she's entered the realm of comprehension.
Vocal performance. Today Nellianne woke up sounding like a 13 year old boy. She has made deep, growly "I am Batman" sounds and high pitched Aria trills. I think she just realized she has a vocal range.
Refined hearing. She heard the birds tweeting during breakfast and kept pointing out the window. Then she'd hunch over, make her silly little excited face and put one finger in front of her mouth - indicating "shhh." She totally digs the singing birds of spring time! :)