Children travelling by train alone

FBaby

My DD12 and DS9 will be taking the train on their own weekly from next Friday. It is however a much shorter journey (1/2 hour). We have spoken about it and they are both happy to do it. I have considered it on the basis that both are mature and confident children. What made it ok for me is the fact that my son has just started walking on his own to a number of places and therefore reached enough confidence to be ok with such situation. Even though he will be close to his sister, I didn't want her to take on the role and responsibility of being a parent to him.

There are a number of stops in between, but it is a route they are very familiar with. It will be rush hour but I will try to insure they get a seat (most people get off where they will get in) and will only have to walk 2 minutes and cross one street to make it to their dad. They will both have a mobile on them (very cheap one). What is reassuring is that if anything happened, a family member or friend could be to them in less than 10 minutes.

Would I be confortable with them going all the way to London on their own in a years time? Probably, but am glad they will get the chance to get used to local travel first.