Children have very little knowledge about road safety and when they wander unsupervised onto the road, it can be very dangerous. This child wanders onto a street in Coimbatore, India and gets hit by a bike. Thankfully the biker managed to slow down quite a bit and there was no serious injury. The rider obviously did not expect this situation. 

Children should always be supervised in public spaces. There are way too many dangers out there. Moving traffic and vehicles is one such danger. 

There are also concerns on this video clip that the biker was riding too fast. It's difficult to draw conclusions, but posting speed limits clearly on such roads would help.