In an interview with the "Today" show on Wednesday, the Australian star explained that she prefers to enter high-profile events using the back door when joined by daughters Sunday Rose, 10, and Faith Margaret, 7, reports dailymail.co.uk.
"I'm still very protective. They say sometimes you've got to hurt a child in order to help them, but a mother knows when something isn't right," she continued.
She shares her two daughters with husband and singer Keith Urban.
She also shares two adopted children with former husband Tom Cruise - Isabella, 25, and Connor, 23.
(With inputs from agencies.)