Brief Answer:
May be aphthous ulcer, please provide the details

Detailed Answer:
Hello

Thanks for asking on this platform
I can understand your concern.
There can be so many causes of blisters/ulcers on tongue. Common causes are Aphthous ulcer, ulcer due to nutritional deficiency or fungal infection.
I would be better able to help you out if you come back with answer of following questuons-
For how many days these lesions are there?
Is there any other significant problem like fever, loose motion, rashes anywhere else in body?
Is her weight and height appropriate for age?
It would be of more help if you attach an image.
Aphthous ulcer is the most common cause and it responds to treatment with application of local anesthetic/antiseptic solution with multivitamin supplements.
In fungal infection like oral thrush applying antifungal helps.
So, requesting you to answer the questions mentioned for better help.

Regards

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