36 U.S.C. § 109 : US Code - Section 109: Father's Day

      (a) Designation. - The third Sunday in June is Father's Day.
      (b) Proclamation. - The President is requested to issue a
    proclamation - 
        (1) calling on United States Government officials to display
      the flag of the United States on all Government buildings on
      Father's Day;
        (2) inviting State and local governments and the people of the
      United States to observe Father's Day with appropriate
      ceremonies; and
        (3) urging the people of the United States to offer public and
      private expressions of Father's Day to the abiding love and
      gratitude they have for their fathers.