How siblings may react

Brothers and sisters often react in the same way as their parents and the child with cancer, with feelings like fear or anger. Other reactions like jealousy are unique to siblings of a child with cancer.

Like their parents and their brother or sister with cancer, siblings often go through denial when they hear the diagnosis. Sometimes these feelings are so strong that siblings will physically turn away from and refuse to talk about the diagnosis. Denial and avoidance are normal reactions that provide distance from the situation and allow time for siblings to adjust. Some siblings need this time. They will eventually start to absorb the impact of the diagnosis and will let themselves feel other feelings when they are ready.

Once siblings start to grasp the reality of the cancer diagnosis, they often are afraid, anxious and confused. They fear that something they said, did or did not do caused the cancer. They are afraid that they might get cancer also. They become anxious about things they don’t understand, like cancer itself and the tests or treatments their brother or sister has to have. They are worried about their ill brother or sister and are afraid that he or she will die. Siblings often worry about how the entire family will be affected by the diagnosis and how it will disrupt their normal routine.

Siblings may bounce between feeling angry and guilty after a cancer diagnosis. They may feel angry that this has happened to their brother or sister. They might be mad at their parents for spending so much time with the sick brother or sister. They might even be angry at their brother or sister for having cancer and throwing the family into upheaval. Then, they might start feeling guilty about feeling angry. They may even feel guilty because they don’t have cancer and feel that they should be the one who is sick.

Siblings usually do not say they are feeling guilty or why they are feeling this way. They are scared that their parents wouldn’t love them any more if they knew why they were feeling guilty.

Even though siblings feel sad and worried about their brother or sister with cancer, they often feel jealous of all the attention the ill child is receiving. They see the gifts and treats that are given to the ill child. They notice that people only ask about their brother or sister with cancer and don’t ask about them. They may start to feel that their parents are playing favourites with the ill child and letting the child “get away with anything” while they are expected to be good and get extra punishment if they aren’t.

Siblings often feel lonely and isolated both physically and emotionally as their brother or sister goes through diagnosis and treatment for cancer. Parents are often at the hospital and are too tired to talk when they get home, which leaves the siblings alone with their thoughts and fears. The absence of the child with cancer, especially if he or she was close to the siblings, will add to the siblings’ loneliness. Siblings can also feel abandoned or displaced since parents need to spend time at the hospital and the siblings may need to stay at a friend’s house or have other people take them to activities. Along with this loss of attention, siblings report feeling left out and less valued – they feel like they’ve lost their own importance within the family because the child with cancer seems to get all the attention.

A child’s cancer diagnosis can lead to feelings of sadness and depression in siblings. Siblings are genuinely sad that their brother or sister is sick and has to be treated. They are sad that their brother or sister can’t do the things they used to do. And as they watch their parents try to deal with everything that comes with the diagnosis, siblings also feel sad because they realize that normal family life may never be the same again.

When siblings are sad, having a good laugh, being physically active or having a good cry can usually help. If children are not able to handle the sadness, can’t be comforted, are showing personality and behavioural changes, are isolating themselves or are having problems at school, they may have depression. If you think a sibling may be depressed, ask the child’s doctor and a mental health counsellor for help.

Expert review and references

  • American Cancer Society. Children Diagnosed with Cancer: Dealing with Diagnosis. Atlanta, GA: American Cancer Society; 2014.
  • American Society of Clinical Oncology (ASCO). People Living with Cancer: Coping. Alexandria, VA.: American Society of Clinical Oncology (ASCO);
  • Effects on family when your child has cancer. Cancerbackup. Cancerbackup: Children's Cancers. London, UK: Cancerbackup; 2005.
  • CureSearch. Support for Siblings. Bethesda, MD: National Childhood Cancer Foundation & Children's Oncology Group;
  • Houtzager, B.A., Grootenhuis, M.A., Hoekstra-Weebers, J.E.H.M., et al . One month after diagnosis: quality of life, coping and previous functioning in siblings of children with cancer. Child: Care, Health & Development. Oxford, England: Blackwell Scientific Publications; 2005.
  • Houtzager, B.R., Oort, F.J., Hoekstra-Weebers, J.E., et al . Coping and family functioning predict longitudinal psychological adaptation of siblings of childhood cancer patients. Society of Pediatric Psychology. Journal of Pediatric Psychology. Cary, North Carolina: Oxford University Press; 2004.
  • Quin, S . The long-term psychosocial effects of cancer diagnosis and treatment on children and their families. Social Work in Health Care. Informa Healthcare; 2005.
  • Walker, C.L., Wells, L.M., et al . Family-centered psychosocial care. Baggott, C. R., Kelly, K. P., Fochtman, D. et al. Nursing Care of Children and Adolescents with Cancer. 3rd ed. Philadelphia, PA: W. B. Saunders Company; 2002: 15: 365-390.

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