Greetings. He is 12 years and it is normal for him to have pubic hair beginning to grow. He must definitely lose weight and he is probably suffering from childhood obesity - please let him see a qualified dermatologist / endocrinologist and get a detailed evaluation. Encourage him to have lots of fruits and vegetables and encourage exercise. For acne he'll need topical retinoids and more medications - depending on exact nature and grade of acne.
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see a qualified dermatologist near you
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