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A child over the age of two, then warm milky cocoa 15 mins. before bed will help.
A crying baby can be a problem. But a baby does not cry without reason. Make sure the cot is warm before putting the baby to bed.Make sure the baby is warm and comfortable.
Remember that every time you put a baby to bed it is a "separation" from mother. So, cuddles and nursing for a half hour before bed.
Babies do not like bright light; nor do they like total darkness. A soft night-light is best.