In our study, serum FGF21 levels were not only correlated with the children’s stress levels, but also with caregiver anxiety and stress (assessed also as the experiencing by them of serious life events), as the scoring of the questionnaires assessing anxiety (STAI) and stress (PSS and HRSES) correlated with the FGF21 levels of the children under their care. This evidence concerns the gene FGF21 and Anxiety.