My eldest daughter, who is 15, wants to go on a day trip to London to go Ice skating with her friends. The problem is, one of her friends will already be in London, and the other is very unreliable (I reckon she will end up not going), but I'm not sure about her going on a train alone. She would get on one train for roughly an hour and a bit, and then on a tube for one stop, and after this her friend would then meet her. She has done this journey once before with a friend, but I'm not too sure about her alone, I'm just a tad paranoid. What are your opinions?