The next morning Willa awoke to humming that came from the kitchen. She walked out and things went similar to how they had the morning prior, save the note under the mug.
A little while later, Willa opened the fridge to grab the eggs for breakfast. Taped quite obviously to a carton of milk was the note.
"Challenge excepted!" was all the girl said.
Later Philby found the note taped to the shower door. He then proceeded to set it inside her dresser drawer, where she moved it to under his nice tea set they used in the evenings. Soon this became a game that lead to constant giggled and kisses as the two took turns hiding the note for the other to find.