UPDATE: Her fever is at 106.6 and we are at the emergency vet now

A stray cat in my neighborhood had a litter of kittens. After observing them for a few days I noticed that the mom rejected the runt of her litter. She was not responding to her cries or nursing her so I decided it was time to intervene. This kitten is around 3 weeks old so she needs a lot of care right now. I took her to the vet today and she had a 106 degree fever. It went down to 104 by the time that we left, but if it does not continue to go down then we will likely have to go to the emergency room. I am a bit overwhelmed with Gumbus’s and Gracie’s current and upcoming vet expenses, so I am just struggling a bit with this, but this kitten needs care or it won’t survive. Any help would be greatly appreciated just to prepare for this kitten’s vet needs. Please do not feel that you have to donate, but if you do I am incredibly grateful for your help. The main reason I’m able to help these cats so much is because of you guys.