4yr old toddler fever, headache. no cough no mucus. after fever has calm down she plays and eats. shes had fever on and off for 3 days?

My child is ill: As a parent and one who has worked with ill children for many years i can hear the worry in your question. A fever in any young child is reason to be worried. With the fever coming and going and her appearing to be happy and normal without the fever this is probably easily solved. But, i would recommend a complete evaluation at a good health care providers office as soon as possible.

Might need to see dr: Keep track of the time that she has had fever and how high would it reach. A constant fever for 3 days need to be checked to find the source of infection. If is on and off is more difficult to assess. You say is playful and that's very good sign.