In the book we have it starting of with everyone getting sick, etc. So Miranda goes to the hospital to find that it's deserted. So she begins to care for three people. Cutting back on her meals so that her mom and brothers can eat more. Then she has to go to the post office and stuff like that. It's getting better though electricity comes back on in small spurts sometimes.
In the chapters 16-21 you see Miranda growing into a young women putting her family before herself as a strong women would do. She talks about why she is keeping this diary briefly. She say that it is for herself but explains she use to think it was for people of the future. Having to take care of three sick people is one of the hardest things a seventeen year old will have to do. Especially in their conditions. This teaches one that no matter what happens you must stay strong because it's not just your life on the line it's the people around you too.