Holy Moly, FIVE! Wooo hoooo, what a lot of fun!
Your little girl reminds me of my Mazie. She is thin too, despite being a good eater, and my best attempts to fatten her up. She too is cold a lot, AND does her share of "nervous shivering" too.
She loves to wrastle with her chubby crazy sister Kiki, and run and chase with her skin brothers....but after awhile it gets to be too much for her. Then she snuggles up on Daddy's chest, and gives everyone that, "MY DADDY'S not gonna let you get me!!!!" look. So that particular picture looked very familiar to me!