A faithful reader has asked me to write on the subject of jealousy. She grew up in a family full of warmth and easy affection. Then she married, and was startled by the culture of jealousy in her new family. Who was spending time with whom, and how much, and why her, not me? She found it difficult to maneuver family relationships without hurting someone’s feelings.

On the surface, jealousy feels like a finely honed weapon that illuminates the disloyalty or fickleness of someone we care for, or their greed or lack of gratitude. Jealousy is rather more a canary in the coal mine, twittering at the first sign our own weaknesses and insecurities, our fragility. Take the case of the Hello Kitty pencils, 5th grade.

Leigh was my classmate, and she had just about everything Hello Kitty a 10-year-old girl could have. Erasers and stickers, little notes, and super skinny, kitty-emblazoned pink pencils in a pink…