The Perks Family:
* Mr. Perks: The station master, kind and helpful, often giving the children advice and helping them with their adventures.
* Mrs. Perks: A kind and motherly figure who often provides the children with food and comfort.
* Bobbie Perks: The station master's son, a young boy who becomes a close friend of the children.
* Peter Perks: Bobbie's older brother, who is also friendly with the children.
Other Important Characters:
* Old Gentleman: A mysterious and wealthy man who befriends the children and helps them in their times of need. He is later revealed to be the children's father.
* The Porter: A gruff but kind-hearted man who works at the station and often helps the children.
* The "Old Buffer": A grumpy but ultimately kind old man who lives in a nearby cottage and occasionally interacts with the children.
* The "Splendid Gentleman": A wealthy man who befriends the children and helps them find their father.
Note: There are many other minor characters who appear in the story, including other passengers on the train, villagers, and neighbors. However, the characters listed above are considered to be the most important supporting roles.