Boy aged 4: Dad, I've decided to get married.
Dad: Wonderful; do you have a girl in mind?!
Boy: Yes... grandma! She said she loves me, I love her, too...and she's the best cook & story teller in the whole world!
Dad: That's nice, but we have a small problem there!!
Boy: What problem?!
Dad: She happens to be my mother. How can you marry my mother!!
Boy: Why not?! You married mine!!!!