My LO has had a fever all day. It's been up and down. He has no other symptoms to go along with it. He just has really high temperatures. It went up to as high as 104 today. We have just been giving him Tylenol and that would bring it down but a couple hours later it will be back up again. He has not been himself all day. He's lethargic and does not want to play. He's still been drinking water and ate just applesauce and soup. I'm just worried for tonight. How high of a temp do you take a 16 month old to the ER?