Brief Answer:
4 possibilities listed in order of likeliness

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Taking your grand daughters age into consideration we could suspect two main causes for body odor to be most likely among the list of possibilities. They are:

-Precocious puberty: Is early puberty. A hormonal surge which can result in the body odor. A strong body odor is more commonly seen in women who belong to the reproductive age group, but as your grand daughter could have hit puberty early she has been experiencing the bad body odor. Precocious puberty is usually tackled with the help of hormonal therapy

-Poor hygiene: Children at this age are hard to handle, and usually hate showers. Poor hygiene could be another more likely cause resulting in bad body odor, but if at all you are most confident about her hygiene(as mentioned in the block above) then we can rule this out

I would also like to list all the other possible causes for your reference, they are:

-Infections: Bacterial and fungal infections can also easily result in poor body odor, and for this you might need to take her to a doctor. The main cause for the occurrence of these infections are damp or moist underarms or generally not wiping well after a shower. The stagnant moisture results in favorable conditions for the growth of bacteria and/or fungus resulting in the infections

-Hyperhidrosis: Is a condition in which increased amount of perspiration takes place. The use of an antiperspirant might help to a certain extent

A few recommendations:
-Try providing her with an antibacterial soap
-Use talcum powder in the affected regions or even baking powder will do to absorb moisture
-Try to avoid food like peppers, onions, garlic in her diet
-Use a tablespoon of 3% hydrogen peroxide in 250 ml of water and apply to the child's underarms for about 15-20 minutes everyday

I hope you find my response helpful and informative. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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