Katie had an explanation about her relationship among her brother and sister. She explained that they took care of one another. Her sister Lynn always took care of her, and as the second child at home, she always took care of Sammy. We can see that it was a family full of peace and happiness. As I read the book I knew that Lynn always regards Katie as a little child, she helped her to do her assignment after school, and she solve problems and encouraged her when she faced troubles. Refer to Katie, she always thought Lynn was supposed to take care of her, to help with her homework and help her to get straight “A”. Katie‘s job was just took care of Sammy, the calmest boy in the world, all she needs to do was fed him when their parents wasn’t beside and change clothing for him at night, but it all changed since Lynn ill. Lynn lied on bed every day, and she took most time of the day to sleep. She couldn't help Katie doing her homework, which brought a bad grade for her. Lynn get worse that she got too to go to school, so Katie had to play the big sister’s role. She had to feed Lynn iron pills and took care of her, and the same time she also need to assume the work of taking care of her brother. And as the story progressed, Lynn lost her friend—Amber, and she got very upset of being dallied by Amber, Katie saw her sister was in a hard time, so she went to find Amber for revenge. And when Lynn had some requires about some glittery pink polish, Katie went to the store and stole it for Lynn regardless. When Lynn got sick, Katie was person that always make her happy and took care of her.