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The actor, who has three daughters and one step-daughter, said even he can see he is sometimes too cautious in his parenting style.
"I'm probably more protective than I've ever been now that I have children," Damon said, during a press conference for his latest film Contagion.
"My wife's nickname for me is 'Red Alert'. I sometimes check to see if the kids are breathing.
"I tend to be a little overprotective without trying to be a helicopter parent."
Damon's wife Luciana gave birth to the couple's third child, a daughter named Stella Zavala, in December 2010.
Contagion is due out in cinemas on September 9.
Watch Matt Damon in the trailer for Contagion below:
