Molly McCook was a human child in the fourth grade in the year 2151. A student in Miss Malvin's class at the Worley Elementary School in Kenmare County Kerry, Ireland on Earth, Molly sent questions, letters, and drawings to Enterprise.
Molly's question was "When you flush the toilet, where does it go?" and one Captain Archer delegated to chief engineer Charles Tucker. Commander Tucker was not pleased with the captain's selection of questions for him and protested. He ultimately relented and explained to Molly the ship's processes of recycling and biomatter resquencing. (ENT: "Breaking the Ice")