Riddle #312

Question: Two children are born in the same hospital, on the same year, on the same day, and have the same father and mother. But they are not twins.

How is this possible?

Question: What tastes better than it smells?

Question: What goes in the water black and comes out red?

Question: What loses its head in the morning and gets it back at night?

Question: What two things can you never eat for breakfast?

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?