The multiple documents that comprise an award application should tell a single story. Since funder awards normally require some combination of a previous research statement, a biographical essay, and a research proposal, you will want to make sure that all of your essays cohere into a compelling narrative. Each of the documents serves a distinct purpose, of course, but as the reviewers read your materials, you want to provide them with a clear sense of your goals and why you deserve funding.
In your initial application essay drafts, focus primarily on answering the prompts provided in the guidelines. Then, as you revise, work to strengthen the narrative links between your previous research, intellectual biography, and future research plans. With a completed draft of all your documents, consider what story you want your application to tell. Take a step back and start to think about the big picture. What makes you the right person to do your research? What aspects of your previous experience demonstrate that you possess the motivation and capability to accomplish the objectives you set out in your proposal?
As you answer these questions, see if there are ways to revise your documents into complimentary pieces of a compelling and consistent story. Remember that application review appointments with GradFund offer you the opportunity to work one-on-one with a fellowship adviser to brainstorm strategies to maximize the narrative cohesiveness of your essays.