The Blame Game
When a child is diagnosed with OCD, parents start to feel guilty. One parent is sure that if she had stayed home with her child and given him more attention, he wouldn't have developed OCD. Another parent worries that he could have fended off the OCD by not asking for a divorce, and a third gets a "telling off" by an angry grandparent who is sure that the child developed OCD because he was disciplined too harshly. The reality of the situation is that none of these actions cause OCD. You can not "give" a child OCD by yelling at your children, disciplining them, giving them a bit less attention or subjecting them to the stress of divorce. If a child seems to have developed OCD after some of these issues crop up, there is a possibility that the issues are simply making the OCD symptoms more obvious or even worse – but they did not actually cause the original OCD.
So if parenting techniques aren't to blame, what causes OCD in children? There are several possibilities, none of which have been proven as a conclusive cause of OCD.
Scientists have not yet definitively identified a gene that causes OCD. At the same time, they have found that OCD has a strong genetic component. For example, a twins study published in the 1980s (written by Carey and Gottesman in the Archives of Genetic Psychiatry) found a heritability estimate of about 80%, which means that there is a genetic link to OCD. It seems, however, that there is more to the disorder than simply genes.
The child's environment can cause OCD symptoms, but only in that they introduce the child to habits that may be copied later. For example, children who see people around them constantly arranging and rearranging objects may begin to do the same thing themselves.
It is also possible that the child's brain is simply biologically hardwired to function differently than others. One possible way that this can manifest itself is in a lower level of serotonin than normal. Serotonin is a brain chemical that transports messages to and from the nervous system. A person with too little serotonin may develop symptoms of OCD. That is why SSRIs, or selective serotonin reuptake inhibitors, are often used as medication for people with OCD. SSRIs increase the amount of serotonin in the body, which enables the brain's messages to be delivered correctly.
So what causes OCD in children? As of now, we're not sure exactly how all of these factors interconnect, but we do know that parenting techniques were definitely not the cause of your child's OCD. So take heart, and focus on trying to help your child work with the disorder.
OCD Chicago. "What Causes OCD?" https://www.ocdchicago.org/index.php/parents/child/what-causes-ocd
Mayo Clinic. "Obsessive Compulsive Disorder: Causes." https://www.mayoclinic.com/health/obsessive-compulsive-disorder/DS00189/DSECTION=causes