The premier previously refused to allow exemptions after a man was found dead in Montreal.
Some might use the loophole to avoid a fine, Quebec's premier says.
Francois Legault said the curfew was needed to prevent gatherings that have fueled the spread of COVID-19.
Quebec is the first province to impose a curfew in response to COVID-19.
Meanwhile, the premiers have unanimously demanded Ottawa increase health care funding by $28 billion with no strings attached.
“With the numbers we have, it’s unrealistic to think we’ll be able to change the situation in time for Christmas," Francois Legault said.
Prime Minister Justin Trudeau has suggested that if things are not running smoothly in the provinces, his government is not responsible.
The boys were two and five.
She filmed herself being insulted by Quebec hospital staff hours before she died.
The rise in new cases brings the total number of confirmed infections in the province to 76,273.