The missing diaper

Here is a picture of one of the babies I teach.  Her name is Miao Miao and She is a year and a half old.  Even though she rarely smiles she is adorable!  She is really attached to me too.  When class is over and I leave the building I have to sneak out because if she sees me leave she will cry and want me to hold her.  Its really endearing.  What you can't tell from the picture is that she is that her jumper is open in the front and back and she is not wearing a diaper.  I was worried the whole class that she would starting peeing on the floor pads we sit on.  Fortunately she didn't.  But it does bring up an interesting topic for discussion.  The diaper-less babies around here wearing split pants is a common sight that I find a bit disturbing.  A couple days ago I saw a cute little boy also around a year and a half old on the subway wearing split pants and no diaper.  I say "split pants" but really it was more of a cut out because you could see all his front and back.   My first thought was: "What if he starts to poop or pee right here in the subway?"  My next thought was: "Is this sanitary?" and then my third thought was: "I wonder if this child will remember being totally exposed like this and carry emotional scars later?"  I know people here don't think anything of a young child being completely exposed like that but the westerner in me started to feel so uncomfortable that I could no longer look at the cute child.  It started to feel wrong, as if I was participating in some kind of humiliation so I looked away.  That led me to my last and most uncomfortable question: Are there any issues with child molestation or pornography here?  And if so isn't this just inviting perverts to look at your child?  I'm not even sure how to go about asking these questions. However, I have decided that based on sanitary reasons, from now on I will require all babies to wear diapers in class.