So today, I had two observations/experiences with little kids on the train.

First, in the morning to school. This little boy and his parents got into the train, and despite the crowds found a seat. The little boy was on the mom's lap, and was pointing at stuff. Like how he pointed at my scarf and made some sort of noise, and his mom explained it was a scarf. He would ask all sorts of random questions about anything, like the train doors or what's in his lunch box.
Then then then this girl around his age got on, and she pointed at the boy, having never seen him before. Being small, she squeezed through the crowd to the boy. They said hi and all that, and pointed at stuff. Then they got off the same station.
I can only imagine they bump into each other in ten years and fall in love. xP

Second was on the way home. My friend and I got on, and we were next to a stroller. The baby in it suddenly pointed at my bag, specifically to one of the zippers. She then tried to reach out for it, and inched away when she almost touched it. Then she actually grabbed it and started moving it up and down. I was lucky that that pocket had nothing in it. =P
Later in the ride, the dad of the girl noticed my bag, and he asked if I like anime. I'm like "yeah" and he asks me about the upcoming Avatar movie.

So yeah, little kids can be very interesting on trains - a repeated observation I have made.