Brief Answer:
Suggestions below

Detailed Answer:
Hello XXXXXXX

Thanks for writing to us.

I would like to know does she snore daily or once in a while
Does she any history allergy like dust allergy or any?

Snoring can be caused by multiple factors like nasal blockage or deviated nasal septum or posture of body during sleep or overweight or narrow airway passage.
If she is overweight then she needs to lose her weight.
Tell her to sleep on her one side (lateral side). Do not sleep on back side.
Clean pillow or and bed sheets before going bed. Dust can cause nasal blockage.
Maintain sleep hygiene
If she feels nasal blockage or obstruction then she needs to use nasal decongestants.
Lack of sleep or tiredness also can cause this.

Nasal adhesive strips are available to improve nasal airway passage.

I suggest you follow these measures if you will not see any improvement then I suggest you visit an ENT doctor for clinical examination, to rule out the cause and treatment will be decided by doctor according to cause.

If you have any queries I will be happy to help you.
Thank you.

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Brief Answer:
First try few tips

Detailed Answer:
Hello XXXXXXX

I suggest you follow my suggestions for few days like sleep on one side, slight elevation head end of bed.
If she has cold or nasal congestion she can take steam inhalation before going bed.

If you will not see any changes then I suggest you visit an ENT doctor.
if you have any queries I will be happy to help you.
Thank you.

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