In 1838, Archibald became sick. Rather than go back to England, they moved to Australia because they thought the weather would be good for his health. They sailed for Sydney. They arrived there in October 1838. They settled at Windsor. On trips to Sydney, Caroline and Archibald learned about the hard lives of emigrants arriving in the colony. They were particularly concerned for the young women who were arriving without any money. The women did not have any friends or family or jobs to go to. Many women ended up working as prostitutes. Archibald returned to his regiment in 1840. He encouraged his wife to continue her philanthropic efforts.