Who is it?

Question: A rich man suddenly dies from a cut on his finger. The next day, two men appeared and claimed to be his long-lost son. They both fit the description in the will and had all the necessary documents. The family attorney proposed a blood test. One man agreed while the other point blank refused. The one who agreed was arrested for fraud at once. The second man was accepted as the heir. Why?

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: What can be broken but never forgotten?

Question: Which thing that comes once in a year, twice in a week?

Question: You are trying to get your chicken, fox, and wheat to the barn. However, the barn is on the other side of the river. You are on a boat and can only transport one animal or wheat at a time. You must choose carefully not to leave the wrong two together, though. It's either the fox will eat the chicken or the chicken will eat the wheat. How do you take each thing across safely?

Question: During what month do people sleep the least?