Fever can support the immune system's attempt to gain advantage over infectious agents, such as viruses and bacteria, and it makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive. Infectious agents are not the only causes of fever, however.
Your sister's grandson is your great nephew. You are his great aunt (if you are a woman) or his great uncle (if you are a man).
Two weeks after it was revealed that Melania Trump has a secret half-brother, the man has spoken out, saying he would love to get to know the father and half-sisters. Denis Cigelnjak said that once the US presidential election is over, he'd like to have pizza and a drink with his father, Viktor Knavs, and his two half-sisters, Melania Trump and Ines Knavs.