Who am I?

Question: A father and his son are in a car accident and the father dies on the scene, so the father is out of the picture. The son is brought to the hospital and when he arrives, the surgeon said, "I can`t operate on my own son!" Who is the surgeon?

Question: During what month do people sleep the least?

Question: People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?

Question: When is 99 more than 100?

Question: What are the next two letters in the following series and why? WATNTLITFS__

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?