Our Team

Michael McMahan

President & CEO

Michael McMahan joined the Foundation as President and Chief Executive Officer in March of 2023. Prior to joining the Foundation, he worked at the George W. Bush Presidential Center for 11 years. Michael rose from a program manager to vice president of corporate planning and development during that period.

During his time at the Bush Center, Michael oversaw the $335 million “A Charge to Keep” campaign to endow the Bush Center’s work. In addition, he managed various strategic and operational areas of the Bush Center during his tenure. Michael previously served in the George W. Bush administration in the Department of Energy and is a graduate of the University of Texas at Austin and Southern Methodist University’s Dedman School of Law.

Michael is the 11th President in Southwestern Medical Foundation’s more than eighty-year history. He will oversee the Foundation’s strategic priorities and partnerships to continue to build long-term sustained impact in the advancement of medical research, training, and care.

Additionally, Michael is a member of the Mission and Outreach committee for the St. Michael & All Angels Episcopal Church, a member of the Bush Center’s 43 Club, and Senior Advisor & Counsel to the Global War on Terrorism Memorial Foundation.  Michael and his wife Amy live in Dallas with their two children – Maddie (13) and Lewis (10).

Sarah Fletcher

Chief Financial Officer

Sarah Fletcher joined the Foundation as Chief Financial Officer in December 2023. In addition to her role as CFO, Sarah will serve as an officer of the Foundation and oversee the accounting and investment of the Foundation’s $1 billion endowment that supports leading-edge medical research, education, and patient care.  

Sarah brings 10+ years of nonprofit experience to the Foundation. As a strategic CFO, Sarah has led the creation of foundational systems allowing for greater mission impact by the nonprofit organizations she has served. Most recently, she served as Chief Financial and Administrative Officer of Trinity Park Conservancy. 

She began her career at the Federal Reserve Bank of Dallas in the public affairs department where she assisted in creating and disseminating public messaging surrounding significant events such as Y2K and September 11th.  Upon completing her MBA, she worked in commercial real estate, focused on private equity sourcing, underwriting potential deals, and capitalizing investments.   

Sarah holds a BA and MA from Baylor University, and an MBA in Finance from Southern Methodist University’s Cox School of Business. She is a member of Financial Executives International and is an alumnus of Leadership Dallas. 

Many of her leisure activities are influenced by having been born and raised in Baton Rouge, Louisiana. Sarah reserves Saturdays in the Fall to watch her college football teams – LSU Tigers and SMU Mustangs.  She enjoys spending time outdoors, creating floral and botanical designs, cooking Southern dishes, and traveling.  

Monica Castillo

Office Manager

Monica Castillo assumed the position of Office Manager for Southwestern Medical Foundation in May 2023. Prior to this, she gained over 12 years of experience in administrative and operational positions within the Medical Education field. She worked at both Texas Christian University and UNT Health Science Center.

Monica’s role at the Foundation involves overseeing daily operations and establishing efficient office protocols. She proactively takes measures to prevent any potential issues and implements policies and procedures to enhance operational flow while fostering a work environment that is welcoming and inclusive.

Monica is a proud Texan, born and raised in Fort Worth. She holds a Master of Business Administration in Organizational Behavior and Human Resource Management from the University of North Texas. Monica’s love for youth sports is evident as she serves as the Vice President of two youth football leagues. When she’s not busy with work or volunteering, Monica values spending quality time with her husband, Lewis, their three children – Natalie, Nathan, and Noah – and her niece, Camila.

Emily Davis

Sr. Director of Gift and Fund Administration | Corporate Secretary

Emily Davis became the Director of Gift and Fund Administration and Corporate Secretary in July 2018. She was promoted to Senior Director of Fund Administration in 2024. Upon joining the Foundation, Emily brought with her more than 10 years of fundraising experience in education and healthcare to her current role.

In her role at the Foundation, Emily oversees gift and fund administration, which includes managing gift records, supervising gift processing, and making detailed decisions to assess donor intent and properly steward donor gifts.

Emily grew up in Corpus Christi, Texas, earning a Bachelor of Arts in English from Texas A&M University.

Blake Evans

Director of Donor Relations

Blake’s nonprofit career began at the George W. Bush Presidential Center, where she served in an administrative capacity supporting Evaluation and Research, as well as Institute Operations. She has since worked for MoneyGram, MoneyGram Foundation, and UTD’s Center for BrainHealth. Most recently, she served as a program coordinator for Cicero’s Social Impact team.

Blake joined the Foundation in 2020 to serve as Donor Relations Manager and was promoted to Director of Donor Relations in 2023. She strategically organizes a plan to provide stewardship for current and prospective donors, leads planning of Foundation programs and events, and leads affinity group efforts.

Born and raised in New Orleans, Louisiana, Blake moved to Dallas to attend Southern Methodist University. She spent a summer studying in Innsbruck, Austria and graduated Magna Cum Laude from SMU with a degree in Marketing and minors in French and Psychology. Blake loves traveling, painting, and spending time with her husband, Clay, and their dog, Pippa.

Rephael Foster

Senior Financial Analyst | Treasury Manager

Rephael Foster has served as Senior Financial Analyst at Southwestern Medical Foundation since January 2017. In addition, he was promoted to Treasury Manager in January 2022. Prior to joining the Foundation team, he worked at Trimont Real Estate Advisors as Associate Director of Asset Management, where he led the team managing a special situations fund.

As Senior Financial Analyst & Treasure Manager, Rephael supports the Finance and Accounting Team by maintaining the investment and consulting relationships of the portfolio, working with our custodial bank to manage the monthly closings of the investment portfolio, and meeting with current and prospective fund managers. Rephael also works alongside the CFO to manage the Foundation’s treasury accounts.

Rephael is a native Texan, born in Grand Prairie to a large family of seven other siblings. He earned a Bachelor of Science degree in Economics from The University of Texas at Arlington. Rephael lives in Waxahachie with his wife Holly, and three young children, Felicity, Everett, and Penelope. Free time is mostly spent tending to the family garden, matching wits with Holly in a nightly chess game, and the occasional fly fishing excursion to the neighborhood pond.

Trae Holmes, CPA

Managing Director of Accounting

Trae Holmes began his role as Director of Accounting for the Foundation in July 2022 and was promoted to Managing Director of Accounting in 2024. Prior to joining the Foundation, he worked for more than 24 years in the public accounting industry primarily serving non-profit organizations. For the last 10 years he was a Director of outsourced accounting at CliftonLarsonAllen (CLA). Prior to his time at CLA he provided audit, tax and assurance services to non-profit organizations while working at Crowe Horwath. Trae is a Certified Public Accountant (CPA) and member of the AICPA and Texas Society of CPAs.

As Director of Accounting, Trae oversees the day-to-day accounting of the organization while providing additional support to the CFO. He has responsibility over month-end close, including financial statement preparation along with managing the annual audit and tax return filings for the Foundation. Trae also helps prepare financial reports for the Board of Directors and various committees of the Foundation.

Born in Georgia, Trae later attended high school in Indiana and went on to attend Indiana University where he majored in Accounting and Finance. While at Indiana he met his wife, Susan, and they have two kids, Drew and Ella. The family moved to Texas in 2012 and currently reside in Flower Mound.  Much of his free time is spent supporting his kids at various baseball/football fields, and attending theater performances or dance/cheer competitions around DFW. He also enjoys spending time outdoors, hiking, fishing, boating, and attending or watching various sporting events.

Brittany Lebling

Director of Communications

Brittany Lebling joined Southwestern Medical Foundation in 2017. Prior to that, she led change management for global operational initiatives at CBRE and consulted executives on change and communications plans.

Lebling joined the Foundation with the charge to tell its story more broadly through strategic marketing and communications. Leading omnichannel strategies across print, web, email, and social media, she is responsible for connecting the Foundation team, donors, and advocates to the impact of the Foundation’s history and the potential that lies ahead.

Born in Maryland, Lebling has also lived in Houston, Texas, and Dhahran, Saudi Arabia. She earned a Bachelor of Arts degree in Media Arts and Design from James Madison University in Harrisonburg, Virginia. Brittany is a lover of live music and travel and enjoys sharing both with her children.

Dustin Magwire

Digital Media Manager

Dustin Magwire joined the communications team at Southwestern Medical Foundation in January of 2022. He began his career in freelance production as an associate producer, working on the History Channel Production: Most Extreme Airports. After that, he worked for several years in broadcast media promotions throughout Texas before settling into a digital media role at Baylor Scott & White Institute for Rehabilitation.

Dustin joined the Foundation’s communications team to help build its expanding digital communications footprint. He supports the Foundation by connecting donors and advocates to the important mission of driving medical progress forward.

Though he was born in Nebraska and raised in the Kansas City area, Dustin has called Texas home since 2005. He graduated from the University of North Texas with a Bachelor of Arts in Radio, Television, and Film. Dustin enjoys biking, camping, sports, and live music. He is always up for a new outdoor adventure with his wife, Sarah, and their two children, Owen and Ruby.

Lizzy Miller

Donor Relations Manager

Lizzy joined the Foundation as the Donor Relations Manager in September 2023. She has eight years of experience at various non-profit organizations in Dallas, focusing on events, donor stewardship, and communications.

Lizzy is responsible for ensuring the highest level of stewardship to Southwestern Medical Foundation donors, assisting in the development of events and campaigns, and representing the Foundation’s mission to our constituents.

Lizzy grew up in the suburbs of Dallas and earned a Bachelor of Arts degree in Journalism from the University of Arkansas. Lizzy loves reading, running, and spending time with friends and family.

Paget Paul

Assistant to the President and CEO | Donor Relations Associate

Paget joined Southwestern Medical Foundation in November 2020 to provide high-level administrative support and calendar management to the President and CEO. Her frequent communication with board members, donors, and partners allows her to build and maintain relationships, which are of utmost importance to her and the Foundation. In 2024, Paget was promoted to an expanded role supporting the donor relations team.

Although Paget was born in Pennsylvania, she considers herself a Texan since moving to the Dallas area at a young age.  Most of her career was as a Legal Assistant, and then a few years working as a Texas Realtor before coming to the Foundation.  She and her husband, Blaine, enjoy traveling, especially to beach destinations.  Their blended family includes three sons, Colton, Josh, and Walker, and a daughter, Kaity.  Besides traveling, Paget enjoys reading, home improvement projects, and spending time with friends and family.

Patricia Rataphan

Gift Processing & Records Manager

Patricia joined the Foundation as the Gift Processing and Records Manager in August 2023. She has experience at various non-profit organizations in the metroplex, focusing on donor development, marketing, and operations. Before coming to the Foundation, her previous role was Director of Operations at Prestonwood Pregnancy Center, where she was responsible for maintaining the organization’s policies and procedures, data integrity and reporting, and project management. 

Patricia’s role at SWMF is responsible for gift processing, gift recording, and donor acknowledgment. She is also entrusted with managing and maintaining the Foundation’s donor database to ensure the highest level of integrity. This includes maintaining regulatory compliance and ensuring that grants are allocated in alignment with donor gift intent. 

Patricia holds a bachelor’s degree in marketing from the University of North Texas. A native Texan raised in Richardson, she currently resides there with her husband, Natt, and their two sons, Wren and Madden. In her free time, Patricia enjoys live music and exploring new restaurants and dessert spots. 

Matthew Scott

Staff Accountant

Matthew Scott assumed the role of Staff Accountant at Southwestern Medical Foundation in October 2023. Prior to joining the Foundation, he gained experience as a Public Accountant specializing in assurance services at RSM US LLP.

In his current position at Southwestern Medical Foundation, Matthew oversees day-to-day accounting operations and provides additional support to the Director of Accounting and the CFO.

A Texas native, Matthew was born in Corpus Christi and made several moves around the state before making Dallas his home in 2017. He holds a master’s degree in accounting from the University of Texas at Dallas and is actively working towards obtaining his CPA license. During his free time, Matthew enjoys spending time with his family and friends, catching a Rangers game, or going to the gym.

Stephanie Vidikan

Senior Director of Operations

Stephanie Vidikan joined the Foundation in 2015 upon moving to Dallas from Washington, D.C. Prior to working at the Foundation, she oversaw operations for 1776, a global incubator and co-working space for startups in healthcare, transportation, education, and financial services.

Stephanie oversees project management for the Foundation, collaborating with the leadership team and external partners to drive progress toward each of the Foundation’s key objectives. She is focused on developing, driving execution, and measuring the impact of the Foundation’s strategic goals.

Stephanie earned a Bachelor of Arts degree in International Studies from Centre College in Danville, KY, and studied in Mexico, Western Europe, and Morocco. She enjoys exploring new areas around the Dallas area with her husband, Michael, and her two sons, Akiva and Jacob.