OCD and other anxiety disorders are fairly common in children but are rarely diagnosed before school age. Many behaviours that in older kids are deemed abnormal are developmentally normal in young children (such as self stimulatory behaviours and rigidity). If any behaviour is interfering with children’s development or functioning they should be investigated and treated. If a 2-year-old is exhibiting OCD-like behaviours, I’d suggest the parents gently redirect or distract them. It may also be worthwhile to investigate any family issues that may be the underlying worry for the child.