Weet-Bix Day is celebrated on the third Wednesday of October to honor the popular whole-grain wheat cereal, Weet-Bix, which is especially beloved in New Zealand and Australia. The day was suggested by Harrison Stanley and aims to recognize the cereal's nutritional value and cultural significance. Typical customs include enjoying a bowl of Weet-Bix with milk, fresh fruit, or other toppings, and getting creative with different serving ideas, such as making breakfast trifles or warming the cereal like oatmeal. The celebration aligns with the pop culture concept of "Weet-Bix Wednesday," and participants are encouraged to share their experiences using the hashtag #WeetBixDay.