“Keep your penis pointing down, Kyen,” I say for the third time. I’m squatting on the floor of the airport family bathroom face-to-face with my two-year-old with both hands on his naked knees to hold his newly potty-trained body steady. “What’s this, Mom?” my four-year-old, Mav, asks. I look left to see what he has gotten into, praying it isn’t the tampon garbage or one of the many other gross things little boys can’t help …