Shouldn't the president's children be off limits?

George W. Bush's daughters were rumored to be fond of parties during their father's term in office, but the first family went out of its way to protect their privacy.

Bill and Hillary Clinton's daughter Chelsea was cloistered away from the public when her father served in the White House.

Jimmy Carter's daughter Amy was widely recognized but not much covered by the national media.

The Obamas have also chosen to keep their daughters, Sasha and Malia, largely out of the public eye. They've enrolled them in Sidwell Friends, the same private school Chelsea Clinton attended, to protect their privacy and asked the media to keep away from the daughters when they're not out on official business with the president.

Of course, there are times when the Obama daughters are front and center for the cameras. When the Obamas make their annual Thanksgiving visit to feed the homeless or when the family engages in national service activities, the daughers are usually in tow. When the president flew to Russia and Africa earlier this summer, the Obama daughters also tagged along for the ride. And of course they were front and center on election night and the president's inauguration.

But does that make them fair game for advertising campaigns?

No, says Daily Voice syndicated blogger Joni Reynolds, who says they "should not be the targets of partisan sniping." Reynolds points to a conservative blog site that recently called the president's daughter a "repulsive name" and, on the other side, a presumably liberal group that mentions the first daughters in an advertising campaign.

"Why are these little girls targets?" Reynolds asks. "President Obama is fair game, not his children. They should not be the targets of partisan sniping."

The new ad was placed in Union Station by the Physicians Committee for Responsible Medicine, according to Politico.com. The ad features 8-year-old Jasmine Messiah asking the question: "President Obama's daughters get healthy school lunches. Why don't I?"

Jasmine, a vegeterian, has also reportedly written a letter to Sasha and Malia, asking them to sign a petition to Congress calling for more vegan, vegetarian and nondairy food options in public schools.

"A lot of schools, including mine, don't offer enough healthy fruits, vegetables and vegetarian meals," Jasmine said in her message to the Obama girls. "I'm glad that your school, Sidwell Friends, already has lots of healthy options in the cafeteria, including vegetarian chili and roasted vegetable pizza. If we work together, we can make sure all students can eat healthy school lunches."

Although the ad campaign may have achieved the group's goal of raising attention to the issue, it's also likely to upset the president who has asked that his kids be left out of the political debates in Washington.