New parents Kristen Bell and Dax Shepard have hit the U.S. TV circuit in an attempt to push a boycott of tabloids which feature paparazzi photos of celebrities and their kids. Actress Bell admits she has become a savage "mama bear" since giving birth last year (13), and she has warned photographers not to get too close to her daughter Lincoln. Now she's urging other celebrities to refuse to pose or agree to be interviewed for publications whose editors buy in family snaps from the paparazzi - and her campaign has reached television. Bell and Shepard appeared on news show Entertainment Tonight on Monday (24Feb14) to push for a total blackout in a bid to hurt publishers who refuse to ignore concerns about celebrity child safety. She said, "I've had (famous) parents tell me that they have to have, like, a mantra for their kids when they're in the car, saying, 'They can't hurt us, they can't hurt us, they're just annoying'. It's just not worth it." Shepard was keen to point out that he and his wife see nothing wrong with celebrities taking photos of their kids and posting them online, insisting sometimes they have no choice. He added, "We think there's a huge difference in a mother photographing her child in the home and 10 strangers chasing a kid on the street. It wasn't taken by a man jumping out of a bush. "A good friend of ours, Josh Duhamel, who's the last guy who would exploit his child for his own popularity, he tweeted a photo of his child because the paparazzi would not leave their gates." Last year (13), Hollywood mums Halle Berry and Jennifer Garner joined forces to fight for new legislation to protect the kids of stars. Their successful campaign led to new laws that restrict what photographers can do around children and how close they can get.