The Railway Children

The Railway Children tells the story of a family who move from London to "The Three Chimneys", a house near the railway in Yorkshire, after the father, who works at the Foreign Office, is imprisoned after being falsely accused of spying. The children befriend an Old Gentleman who regularly takes the 9:15 train near their home, and he tries to help them prove their father's innocence. The family takes care of a Russian exile who came to England looking for his family and Jim, the grandson of the Old Gentleman.
Edith Nesbit (1858-1924) was the author of world famous books for children - the tales of fantastical adventures, journeys back in time and travel to magical worlds.