Simplify the following text for a Grade 14 native English-speaking person.
Original: The Deputy Assistant to the President for National Security Affairs , commonly referred to as the Deputy National Security Advisor , is a member of the Executive Office of the President of the United States , serving as deputy to the President 's National Security Advisor .
Simplified: The Assistant to the President and National Security Advisor is a member of the Executive Office of the President of the United States , serving as deputy to the President 's National Security Advisor .