In the books, there are several families of hedgehogs that make the journey to White Deer Park including Hedgehog, who is the elected leader of the group. The hedgehogs make the journey safely until the animals reach the motorway, when two of the older hedgehogs fall behind during the final crossing and get run over. The rest arrive safely at White Deer Park. They all hibernate throughout the first winter and emerge again in the spring. The original Farthing Wood hedgehogs die of old age before the events of The Siege of White Deer Park, leaving their offspring behind in the park.
The ancestors of the Farthing Wood hedgehogs appear in Farthing Wood: The Adventure Begins, the prequel set five years before the journey to White Deer Park. The most prominent of these is Sage Hedgehog who has several premonitions about the downfall of Farthing Wood and urges the other animals to do all they can to ensure the wood's survival.
In the TV series, only two hedgehogs make the journey to White Deer Park; Hedgehog and Mrs Hedgehog. When the animals reach the motorway, the hedgehogs both panic and only just make it across the first section. When they attempt to cross the second section, Hedgehog panics again and freezes in the middle of the road. Mrs Hedgehog pleads with him to continue, but he is unable to and she stays with him, refusing to leave him behind. As the traffic approaches, they both out of instinct curl up into balls and are run over by a lorry, the other animals unable to save them.