Book request: Read when i was maybe young so 1990 to 2005ish. Magical world where the only child of the king and queen cried a lot. Had 3 triplet sisters as nannies, with red hair and freckles. They loved fish and chips. One day they went through a magic door/ cave, that only opens every 10 years or so for a short time. They accidently left the child behind, and everyone was very sad. Many years later, when the door can open again, a group goes back to find the child. In the group was at least one of the sisters, maybe more, and an elderly wizard, who was in charge. I think they find the child and he helps them to get back to their world. Sorry, thats all i can remember.

Matching book description: A forgotten door on an abandoned railway platform is the entrance to a magical kingdom--an island where humans live happily with feys, mermaids, ogres, and other wonderful creatures. Carefully hidden from the world, the Island is only accessible when the door opens for nine days every nine years. A lot can go wrong in nine days. When the beastly Mrs. Trottle kidnaps the pr A forgotten door on an abandoned railway platform is the entrance to a magical kingdom--an island where humans live happily with feys, mermaids, ogres, and other wonderful creatures. Carefully hidden from the world, the Island is only accessible when the door opens for nine days every nine years. A lot can go wrong in nine days. When the beastly Mrs. Trottle kidnaps the prince of the Island, it's up to a strange band of rescuers to save him. But can an ogre, a hag, a wizard, and a fey really troop around London unnoticed? ...more