Grace Mugabe appeared with her 93-year-old husband on Friday at a political rally ahead of next year’s elections.
Zimbabwe’s government and state media have kept silence on the accusations against the first lady. She returned to Zimbabwe last month after South Africa granted her diplomatic immunity.
Mugabe used her appearance at the rally to criticise ruling party members who publicly declare loyalty to President Robert Mugabe but insult his family behind his back.
She says that “if you insult Mugabe, you will not be blessed”.
The ruling party’s youth leader urged the first lady to discipline youths who “misbehave”.