A WhatsApp voice note sent by a KwaZulu-Natal man who allegedly killed his girlfriend, Bongeka Makhathini, 21, and their three-year-old son Okuhle, accusing her of giving birth to a child that was not his, is believed to be what caused the death of the trio.Mlondi Cele, 24, was found hanging in the lounge of an RDP house in Danganya, uMgababa, south of Durban.Makhathini’s body was found in the bedroom while her son was found metres away. Both the woman and the child had had their throats slit.A distraught Bheki Cele, the former minister of police, who is Mlondi’s uncle, said that at…