Message-based health information dissemination systems can potentially improve maternal and child health (MCH). By conveying health information to parents, SMS- and chatbot-based systems can support parentsâ?? learning and empower them to make better health decisions for their children. However, there is limited design advice for creating message-based dissemination systems for MCH. To help address this gap, we conducted 14 participatory workshops with 42 parents from Portugal and South Africa, exploring how parents learned to care for their childrenâ??s health. Our findings showed how parents reflected on the health advice they received, by assessing the fit of the advice to their childâ??s characteristics, their values and beliefs, the adviceâ??s feasibility, or the intention and competence of the advice giver. Based on these insights, we propose four design implications for creating message-based health information dissemination systems tailored to parents and their children.