* Nature itself: The most prominent antagonist is the wild and unpredictable environment of the deserted island. The family faces dangers from storms, wild animals, and a lack of resources. This constant struggle for survival is a major theme throughout the story.
* Fritz's rebelliousness: The family's teenage son, Fritz, often causes trouble and disobeys his father. His recklessness and immaturity can be seen as a source of conflict and tension within the family.
* The shipwrecked pirates: While they are only briefly encountered, the pirates represent a direct threat to the family's safety and well-being. Their presence highlights the dangers lurking beyond the island.
Instead of a single villain, the story focuses on the family's resilience and resourcefulness in overcoming these challenges, ultimately finding strength in their unity and faith.