Background - School Distress (SD) refers to a young person's difficulty attending school due to the emotional distress experienced as a result of school attendance. It is thought to affect around 1% of school-aged children, although prevalence rates are higher amongst autistic children and young people (CYP). To date, there is limited research into the impact that having a child who experiences SD has on parents, carers, and other family members. Aims - We aim to describe the lived-experience of the parents of CYP experiencing SD in the UK, and quantify the impact of the current status quo on their physical and mental health, and lives more broadly. Method - A concurrent embedded mixed-method design was adopted. The survey link was shared widely via social media in February 2022 and participants were recruited via volunteer-sampling. Participants consisted of parents of CYP who are currently experiencing (n=738), or who had previously experienced (n=209), extreme distress whilst attending school, parents of age-matched CYP without school attendance difficulties (n=149), and parents of CYP who had never attended a school setting (n=25); giving a total of 1121 participants. All participants were currently living in the UK and 97% were mothers. Results - Findings revealed that the experience of SD can have a devastating impact on the mental health of parents, with over half of parents developing a new mental health condition since their child's difficulties began (51.7%). Parents supporting CYP with SD had significantly higher levels of all the negative emotions measured (i.e., anger, anxiety, sadness, disgust, and fear), alongside significantly lower levels of positive emotions (i.e. relaxation and happiness) than parents of age-matched control CYP who did not experience school attendance difficulties. Heightened daily anxiety, stress, and low mood were pervasive, and a significant deleterious impact was reported across all aspects of the parents' lives, including their careers and finances, and their other children. In addition, parents of children experiencing SD reported overwhelmingly negative treatment from professionals, whereby they frequently reported feeling blamed for their child's difficulties, threatened with fines or court action, spoken to in a dismissive and critical manner, and feeling threatened, vulnerable, and disbelieved following interactions with school staff and other professionals (including Children's Social Services, Local Authorities, and CAMHS staff). A lack of support from family, friends, other parents, and work colleagues were also mentioned by many, although others described family, friends, and other parents with similar lived experiences to be their most important sources of support. Finally, parents of CYP currently experiencing SD rated the experience of a child school-refusing as the second most threatening life event, superseded only by the death of a first-degree relative, including a child or a spouse. Conclusions - This study highlights a bleak, adversarial, and lonely picture for the parents of CYP struggling to attend school. More specifically, the findings depict a system rife with parental blame; a system that appears to isolate parents through hostile, threatening, and punitive actions. A wider lack of societal understanding of the experience of School Distress further compounds this dearth of support for parents, placing parental mental health in further peril.