Unless the Council shall, by four-fifths vote of the members elect thereof, other than the member involved, which vote shall be recorded as part of the official proceedings, determine that the best interests of the City shall be served, the following relatives of any elective or appointive officer as defined in Section 4.6 of this Charter are disqualified from holding any appointive office or City employment during the term for which said officer was elected or appointed: spouse, child, parent, grandchild, grandparent, brother, sister, half-brother or half-sister, or the spouse of any of these. All relationships shall include those arising from adoption. This section shall in no way disqualify such relatives or their spouses who are bona fide appointive officers or employees of the City at the time of the election or appointment of said official.