Suffering from a chronic disease (CD) in adolescence can significantly impact the emotional health of adolescents and their families. MHealth can be a useful tool for these groups. However, few intervention programmes include the family system. The aim is to design an intervention programme (10Vida) for a paediatric population with a CD, and their families, to improve their adaptation to the disease. The study is a quasi-experimental repeated measures design in a open study, where the patients themselves, and their families, are their own control group. Participants will receive an intervention of seven individual sessions: five sessions with each patient, and two sessions with their caregivers. In the case of the patients, the aim is to improve their emotional state, their self-esteem, and their emotional competencies, reducing their perceived threat of illness. Furthermore, in the case of the caregivers, the aim is to improve their emotional state and reduce their burden. Indirectly, working with caregivers and those being cared for will improve family ties. The pilot study will involve 25 to 30 chronically ill adolescents aged between 12 and 16 years and their primary caregivers. Following the results, the necessary modifications will be included, and the programme will be offered to adolescents and their families who are willing to participate.