Princess Pouty

How old is my daughter? Sometimes it's hard to tell. About two days ago, she started doing something new. When she would get in trouble for something or get told to do something she didn't want to do (share with brother), her eyes water up and her fat pouty lip comes out. Now she just looks at me one last time before turning on her heels and marching somewhere to pout by herself. Twice she was on the landing stairs, just sitting there and pouting. Once, she went to the dark, unlit bathroom to pout. When she gets it together, she comes back in the main room with the rest of us. I didn't tell her to do this, she just did. But now, if she starts crying, I ask her if she needs to go to a quiet place to calm down and surprisingly she does most of the time. And when she is done, she comes out and announces, "I'm calm now, Mommy!"