There was 2 children

Question: There were 2 children, the son and the daughter. The daughter was born on January 20th and the son was born on March 12th. Both of them were born in the morning. Which one did their parents see first?

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: During what month do people sleep the least?

Question: When is 99 more than 100?

Question: What can be broken but never forgotten?

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