Thanks for providing more information.
I understand your concern about your child as she is not sleeping well and as you are a mother so this can be a worrisome for you.
As per your description,she may have Obstructive Sleep apnea due to Enlarged Adenoids.
And Adenoidectomy can be helpful in such cases.
However as she is scheduled for adenoids removal in December so in my opinion,you should consult her doctor again to get some steroid medications to reduce some inflammation of adenoids which relieve sleep apnea.
Usually Dimetapp Elixir should be given for short period of time.
And it's good to use it 2-3 days when her symptoms gets worse and discontinue it.
You can try a humidifier in your room.
Also elevate her head side of bed.
Give her warm liquids.
And make an appointment with her doctor and discuss her current symptoms for proper treatment.
Hope this helps.
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