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).
Quick Answer. Your grandfather's brother is your great-uncle, and you are his great-nephew or great-niece. Your great-uncle's children are your second cousins because you share common great-grandparents, just as you share common grandparents with your first cousins. Continue Reading.