"Kayla will always have a special place in the history of Arizona, and we are deeply saddened by her loss," said D-backs president and CEO Derrick Hall. "The way in which she helped others and gave back to the world around her embodied many of the core values of our organization and our players will undoubtedly be proud to wear her name on their sleeves."
Mueller, 26, attended Tri-City College Prep High School and then Northern Arizona University, where she studied political science and focused on international issues in and out of the classroom. After graduation, she traveled around the world, volunteering with several humanitarian groups and teaching young children abroad.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.