Cornelia de Lange syndrome is a very rare genetic disorder which is present from birth and can lead to severe developmental anomalies. It affects both the physical and intellectual development of a child. Characteristics include delayed or limited speech development (in some cases there is a complete absence of any speech); poor expressive communication; repetitive behaviours, e.g. stereotyped, compulsive and ritualised behaviours that occur in the same way repeatedly; social impairments, e.g. avoiding eye contact, not sharing attention with others, rejection of physical contact; many individuals are described as restless, overactive, distractible and irritable; self-injurious behaviour is also common e.g. hand-biting, head-slapping, and eye-poking.