What do you get when you mix two young children, one tired mom, and a Christmas to-do list? Definitely not peace on Earth. “Don’t step there!” My hand jerked toward my toddler’s ankles, but too late. Her foot crunched a row of Christmas ornaments arranged meticulously on the rug, prepped for hanging. “I sorry, Momma!” Her sock hovered over a sparkly blue star, crushed into five pieces. “I told you to stay on the sofa! Sweetie, if you want to help Mommy decorate the tree, you need to be very careful around the ornaments. Now it’s broken.” Her bottom lip …