When digging out a drain, the little yellow digger gets stuck in the mud. So they bring in a bigger digger . . . The story of The Little Yellow Digger was created from a real event, when one of Betty and Alan's grandchildren excitedly told them about a digger getting stuck in the mud next to their house and they had to bring a 'bigger digger' to help free it. The idea stayed with Betty and The Little Yellow Digger was eventually born.