Brief Answer:
Continue Tylenol,Underlying cause of fever should be evaluated

Detailed Answer:
Hello

Thanks for the query

The most common cause of high grade fever without any specific associated symptoms is viral infection.In viral infection child usually get normal(active/playful) in between the febrile period.
Most of the infection, viral or bacterial initially manifest as fever only(fever is a protective inflammatory response to infection).The fever should be managed with antipyratic(like tylenol) and tepid sponging.
In most of the viral infection fever usually starts declining in severity or frequency after 4-5 days.Make a temperature chart to monitor the pattern of fever.
Most common viral infection is upper respiratory tract infection.This should be managed with antiallergic/decongestant syrup.
So I would suggest you to monitor the temperature and keep an eye for the appearance of new symptoms(cough/cold,burning micturition,loose motion,fast breathing,throat pain).Till then give tylenol. Also do tepid sponging and give plenty of fluids,this helps in fast relieve of temperature.
If fever persists or condition deteriorates consult your pediatrician.

I would be glad to answer if you have any more query.
Wish your child good health.
Regards

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