Well personal factors could include reasons such as lack of stimulation or affection from parents, mental health problem, abuse, emotional or behavioural problems, a child witnessing domestic violence could affect how a child develops...in young children bed wetting & tantrums, lack of concentration at school and behavioural problems.
External could be the environment where the child lives (poor ~ run down), children living in war torn countries or countries where natural disaters are commomn, these things are external, also culture and religion can affect a child, they may speak one language at home & find it difficult to understand English at school which will affect their learning capacity.
Hope that gives you a few ideas
Tracy x
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