Who is Laura Fountain from If the Witness Lied and what is their importance?

Laura Fountain is the mother of the Fountain children. When she is pregnant with Tris, she finds out she has cancer. She refuses cancer treatment in order to save her baby. This captures the attention of the local news media and puts the Fountain family in the middle of a hot debate. Shortly after giving birth to Tris, Laura is ready to start her chemo treatments, but her health spirals downward and she dies.