Shielding the children of presidents isn’t necessarily tradition: some presidential children worked at the White House, others were active on the campaign trail.

The Obama girls are the youngest children in the White House since Amy Carter in the 1970s. The first family has released family photographs of the two, pardoning the National Thanksgiving Turkey, Christmas shopping with their dad and touring South Africa with their mom.

It was first lady Jacqueline Kennedy, who after studying presidential children, insisted that her son and daughter not be public figures, said Doug Wead, a staffer in the George H.W. Bush White House who wrote about what he called the “triumph and tragedy” of first families in the book “All the Presidents’ Children.”

“She concluded that without many exceptions, the most successful children were removed from the White House and the limelight,” Wead said, noting that the Obamas may be tweaking the tradition with the appearance of the girls in advertising material.

Obama often has reached to his daughters to personalize his thinking.

During the BP oil spill in 2010, he cited Malia to voice his frustration about the ongoing leak: "I woke up this morning and I’m shaving, and Malia knocks on my bathroom door and she peeks in her head and she says, ’Did you plug the hole yet, Daddy?’"

In the Father’s Day piece, Sasha and Malia appear in photographs and on video that appears to have been filmed on the campaign trail, clowning around with their dad. In the television ad, they appear in photographs.

The ad, “First Law,” targets female voters, touting Obama’s decision to sign the Lilly Ledbetter Fair Pay Act on his first day in office. The 30-second spot is playing in seven swing states: Iowa, Colorado, Florida, North Carolina, Nevada, Ohio and Virginia, where female voters could make a difference in what’s expected to be a close election.

One photograph of the sisters with their father appears after a picture of Obama and his mother flashes on the screen. A female narrator says, “The son of a single mom. Proud father of two daughters. President Obama knows that women being paid 77 cents on the dollar for doing the same work as men isn’t just unfair, it hurts families.”

The girls also appear at the close of the ads, holding hands with both their parents.

Iowa-based pollster J. Ann Selzer suggested that the inclusion of the girls plays into the political battle for women’s votes. “It’s part of that wanting to connect to moms, one of the ways in which the campaign is signaling, ‘President Obama understands women,’ ” she said.

The family appeal is also a way of creating a buffer that negative ads “can have a tough time cracking,” Selzer said.

“This is the human side: ‘Here is my family. I’m an average guy just like you,’ ” she said. “The use of the girls does not seem by accident.”