The Fault in Our Stars has elements that are based on real - life situations. Author John Green was inspired by his time working in a hospital with young cancer patients. He incorporated their stories, emotions, and the unique challenges they face into the book. For example, the main characters' experiences with illness, their relationships with family and friends, and their search for meaning in the face of mortality are all things that real young cancer patients might go through.
One possible fault could be that the character development wasn't as deep as it could have been. It felt a bit rushed at times, leaving you wanting more depth.