The goal of this observational study is to learn about the impact of Marfan syndrome (MFS) in paediatric affected subjects. the main questions it aims to answer are: * The assessment of quality of life in MFS Italian patients; * The impact of phenotypic manifestations on self-image and self-management skills; * Stratify patients according to the need of psychological support. Participants will take part in the study by completing four self-report questionnaires.