“…There are specific physical characteristics of Down syndrome (e.g., those associated with sleep disorders) (Richdale, Francis, Gavidia-Payne & Cotton, 2000;Stores, 1993) as well as a higher incidence of illness (Roizen, 1996) that may significantly impact the behavioural repertoires, including increasing the likelihood of challenging behaviour, in children with Down syndrome. Researchers have also demonstrated that challenging behaviour, particularly avoidance behaviour, appears consistently in very young infants with Down syndrome (Wishart, 1993a(Wishart, , 1993b.…”