A person is not eligible for appointment to the board if the person is:
(1) an employee of Cameron County;
(2) an employee of a municipality located in the district;
(3) a district employee; or
(4) related within the third degree of consanguinity or affinity, as determined under Subchapter B, Chapter 573, Government Code, to a member of the Commissioners Court of Cameron County, to a member of the governing body of a municipality located in the district, or to a person described by Subdivision (1), (2), or (3).