Relation Between Son, Father And Mother

Son : Daddy, I fell in love & want to date this awesome girl. Father : That's great son. Who is she? Son : It's Sandra, the neighbour's daughter. Father : Ohhh I wish you hadn't said that. I have to tell you something son, but you must promise not to tell your mother. Sandra is actually your sister. The boy is naturally bummed out; but a couple of months later : Son : Daddy, I fell in love again and she is even hotter! Father : That's great son. Who is she? Son : It's Angela, the other neighbour's daughter. Father : Ohhhh I wish you hadn't said that. Angela is also your sister. This went on couple of times and son was so mad, He went straight to his mother crying. Son : Mum I am so mad at dad! I fell in love with six girls but I can't date any of them because dad is their father! The mother hugs him affectionately and says : My love, You can date whoever you want. He isn't your Father..!!