I was scratching my nephew's back for him. He pulled his shirt up and told me to scratch inside. He looked in the mirror and saw his nipple. He went, "Huh?" Put his finger on his nipple and said, "Flea mountain." I was like, "Flea mountain?" He replied, "Yes, flea climbs on mountain." I was cracking up inside but tried not show it. Should I have told him it's called a nipple? Frankly, I got no idea where he got that term.