I'll Always Be Your Friend by Sam McBratney

No one likes to stop playing when they're having fun. So when Mother fox says its time to go home, her little fox tells her, "I'm not your friend anymore," and scampers off. But as daylight fades and dark shadows loom, little fox starts to have second thoughts.

With his usual keen eye for the range of emotions of young children, Sam McBralney perfectly captures the trust between a child testing out his independence and his mother, who reassures him "I'll always be your friend."