My 1 year old will be getting his DTAP second shot tomorrow. I had been worried about him running a fever, so to prevent that, I made sure he only has one shot per visit. I also give him infant tylenol right after his shot, whether or not he has a fever.  In addition, I give him infant vit. c, a high dose, and he also gets cod liver oil, for Vit. A. The vaccine research I’ve been doing says that supplements like this help prevent severe reactions and boost children’s immune system. I hope this helps.