New research estimates that a third of toddlers between the ages of three and four in low and middle income countries fail to reach their development milestones.And in SA the number stood at 579‚900 or 26% of children in that age range.The research‚ published on Tuesday by Harvard University's TH Chan School of Public Health‚ found that these children fail to develop essential skills to maintain attention‚ follow simple directions‚ communicate and get along‚ control aggression‚ and solve progressively complex problems.The research draws on data provided by the caregivers of almost 100‚000 children in 35 countries and estimates that 81 million of the roughly 240 million pre-schoolers in 135 low to middle income countries struggle to reach milestones in early childhood.Researchers said this is associated with later development‚ mental and physical health‚ better learning in school and more productive lives as adults.The South African figures in the research are from 2010 and reflect low Early Childhood Development Index (ECDI) scores in 579‚ 900 three to four-year-olds.ECDI is a caregiver-reported index of ten yes/no questions designed for children to assess four domains of development - literacy-numeracy‚ learning/cognition‚ physical health and socio-emotional development.Professor Elizabeth Henning of the University of Johannesburg's education faculty said that the research suggests that poor kids don't develop as they should‚ but warned that results such as these are deeply contextual.For example‚ results would differ in rural Sudan and Johannesburg‚ she said.“Most of early childhood development is about good nutrition‚ security and [children having] no toxic stress‚” she said.In these environments children flourish‚ but hope is not lost for little South Africans who have had a rough start.“The good news is [that when] help is given while the child is growing‚ much of that can be remedied‚” Henning said.She also said that while the results are likely to be true she remained sceptical‚ saying that it was difficult to cognitive development in the three to four year age group because “pretty good tests” were needed.She said that ECDI measures literacy and numeracy in children‚ but that in her experience mathematics skills cannot be determined in children at the ages of three and four.Harvard University's researchers said that the problem of poor early childhood development was most acute in sub-Saharan Africa with 29.4 million children not reaching their development milestones.This was followed by South Asia and the East Asia and Pacific region...