Embrace your inner grouch and wear green for National Grouch Day on October 15! This Sesame Street-inspired holiday has been celebrated since at least 1976. Whether you’re a fan of a beloved Muppet, love to grumble or just enjoy a fun excuse to celebrate, this day is the perfect time to get grumbly in green. Remember to snap a pic and share your grouchy look with @ntctimberwolves.