Stress attack at my house

My 3 year old has been running a fever for the past few days and it started spiking higher. So I scheduled a Dr's appointment and my dear hubby took her for me. They can't find any obvious things wrong, so they drew some blood, ordered a chest x-ray, and they want a urine sample (easier said than done!!!!) She is getting pretty dehydrated because she refuses to eat or drink much. We have been potty training so I had taken her sippy cup away so that we could have success. So my mission for the next 24 hours is to force liquids and if she doesn't get enough, she will be admitted to the hospital for rehydration and further tests. Just what you need when you are 9 months pregnant. I pray it is nothing serious but want to know that there is something wrong. You can see pain on her face and when you can't fix it, you just want to cry. Anyway, I will keep you posted.