Brief Answer:
heat rash most likely..

Detailed Answer:
Hello XXXXXXX Welcome to HCM..

I've gone through your query and reviewed those images , it looks like heat rash only(you may be knowing this as prickly heat)..

This is a mostly self-limiting condition..

Are the rashes only over the forehead ? Do they itch ? any other associated complaints ?

The most important advice is to keep the area dry, avoid rubbing too much(staying in side the Air-conditioning will help), don't itch, don't let her touch them with the nail otherwise they might get infected..

Please tell her to take Cold water bath twice to thrice daily during this season..

Apply Lacto-calamine lotion over the affected area three to four times day..

Eat and drink foods with cooling effects like Yogurt, butter milk , lemonade , cucumber, watermelon etc..it'll help to sooth..

Drink a lot of water (3.5 - 4 ltr per day for the time being)..

Avoid direct sunlight exposure as much as possible..

With all these, she should be feeling better within a few days only..

Don't worry..

In case the rashes persist for more than a week or get excessively itchy, please consult a Dermatologist for a detailed physical examination..

Hope my advice will clarify your doubts, let me know if you have any ..

Take Care
Kind regards

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