Deep disgust in the train

Last night I was riding the train home, and at one point a young lady came on board with her son, a boy of perhaps three years of age.  From the very begining, this toddler was such a pain in the ass... anything he wanted to talk to his mom, he had to yell to the top of his lungs even though his mom's ear was a few inches away.

At one point this little devil decided he needed to pee.  He was yelling and started to take his dick out.  What did his mother do?  She took out a plastic bag, and let him take a leak into it.  Yeah, right in the middle of the train.  When he was done, she tied a knot on the bag, and then tossed it to one corner of the train.

What the fuck?  And all of the other, local, people were watching too, but from the look in their eyes, it looked like they thought that was cute!  Was that some sort of candid camera or something?