Neither the City Manager, the Council, any department head, nor any other authority of the City government may appoint, elect or employ any person related to any Council member, the City Manager, or to himself, or in the case of a plural authority, to one of its members, by blood or marriage, within the third degree, including step-relationships or in-law relationships within the third degree, to any office or position of profit in the City government; but this shall not prohibit any person employed by the City at the effective date of this Charter from continuing their employment and being promoted therein.