Families often have little knowledge and skills to support their trans children. Therefore, our aim was to learn more about the experiences of parents of trans children and adolescents and how the transition process is experienced. Using a qualitative approach, we analyzed 22 life stories written by parents of trans children and adolescents. The data were analyzed with MAXQDA. Three key periods were considered: (1) before, (2) during, and (3) after social transition. The themes most frequently reported by parents were: children’s not expected gender expressions and negative attitudes and feelings, and parents’ negative feelings, denial and repression attitudes, confussion and search of information, before transition; children’s explicit disclosure, name selection and more positive attitudes, followed by parental understanding, acceptance and support, during transition; and both parents’ and children’s positive attitudes and feelings, as well as concern about pubertal development and expectations and fears about the future, after transition. In general, the stories reflect children’s negative emotions before social transition and parents’ doubts and lack of knowledge, which were followed by acceptance and more positive emotions once the social transition had taken place. Concerns and problems were reported by most of the families throughout the three time periods. Our findings emphasize the need to facilitate social transition and to design specific approaches to better support transitioning children and adolescents, and their families.