When their home next to a brook is destroyed by beavers, a large family of golden mice is aided by Poppy the deer mouse and her grumpy porcupine friend, who in the process forges a relationship with the son he had abandoned.

Feeling neglected on his birthday, Ereth, the cantankerous old porcupine, sets out looking for his favorite treat and instead finds himself acting as "mother" to three young fox kits.