Older children, younger children, and contemporaries all have their uses,... The great use of older children is to provide attainable ambitions. A child will make tremendous efforts to be thought worthy of joining in an older child's game.... A child will be cheerfully submissive to an older brother or sister, in a way which would be impossible towards an adult, except as a result of excessive discipline.
Source: On Education, especially in early childhood, 1926
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