Humpty Doo and the Coolabah Gully

In Humpty Doo book two, Jinx Valentine is reunited with her Humpty Doo friends. The children are staying at the prized swimming spot, Coolabah Gully, and also minding Mona the elephant. Their holiday is upset when Mona starts trespassing, stealing people's rubbish, and swimming 'til all hours.
When Mona follows a roaming pony into the bush, the children run after her and get hopelessly lost. Navigating the bush will put them to the test, and they meet several strange characters along the way! But the real drama is lurking back at the Gully, or rather under it. What unfolds will change the children forever.