Wilson’s disease is a rare autosomal recessive disorder (prevalence 1 : 30,000) caused by pathogenic variants in the ATP7B gene (OMIM 277900). Early diagnosis and pathogenetic therapy enable stable remission. Poor treatment adherence is the key factor adversely affecting the prognosis. This family case study has demonstrated that inadequate attitude towards therapy contributes to the progression of organ damage and increases the risk of disability and mortality. Clinical observation confirms a direct link between compliance with the treatment regimen and clinical outcomes.