trend_tok_hub on Instagram: "The post is a humorous riddle video showing a man using a marker to draw X and O on stacks of clean diapers, overlaid with "In case your grandma didn't teach you," prompting speculation on its purpose amid 1.7 million views. Top replies reveal a practical intent: marking diapers helps parents track changes at daycare, ensuring caregivers swap them regularly rather than waiting until pickup, as shared by users with firsthand experience. Alternative explanations includ