Riddle #65

Question: There are 2 fathers and 2 sons going on a fishing trip. Every person catches one fish. In total, there were only 3 fish. How is that so?

Question: What do you get when you cross a witch with sand?

Question: What do you call a sad bird?

Question: What kinds of balls do dragons play soccer with?

Question: What can be broken but never forgotten?

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?