"I used to have a terrible habit," Tabby admitted in a conspiratorial tone. I pressed the phone closer to my ear. "Go on." She took a deep breath. "I used to be horrible about not knocking on closed doors. Just barged right in. Then Mom told me I needed to practice by always knocking on every door before I came in. Next thing I knew my habit had gone the other way. I caught myself knocking on my closet door before opening it to select an outfit. But, worst of all, I knocked on doors to rooms I was leaving." She never told me the sad ending to her tale--whether she's been able to break these new habits or whether they plague her still.