"I`m not going to drink my own mother`s blood!" I yelled. "That`s disgusting!" "You can drink my blood if you want," Zach chimed in. "I`ll even let you bite me." "No biting," Mum said. "It wouldn`t be sanitary." "What do you think I`ve got, rabies?" I said to her in indignation, then turned to Zach. "And, no!" "Why not?"…