Indulgent grandparents may be bad for their grandchildren's health. The study, looking at cancer risk factors, suggests grandparents are often inclined to treat and overfeed children, and found some were smoking in front of their grandchildren and not giving them sufficient exercise.

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Indulgent grandparents may be bad for their grandchildren's health. The study, looking at cancer risk factors, suggests grandparents are often inclined to treat and overfeed children, and found some were smoking in front of their grandchildren and not giving them sufficient exercise.