BOSTON — Every generation or so, the news media redefine what is and is not fair game in how they cover the personal lives of people in politics.

Seven decades ago, the press decided that it would keep one of Franklin D. Roosevelt's secrets. It didn't photograph him in his wheelchair or write about his paralysis, and most of the country never knew he couldn't walk.

Nearly a half-century ago, the media reaffirmed the zone of privacy allowed presidents, deciding not to pursue stories about John F. Kennedy's womanizing. His affairs weren't known publicly till long after his death.

Twenty years ago, the media changed the rules, writing about Democratic presidential candidate Gary Hart's night with a woman not his wife. That was reaffirmed, and accelerated, in news stories about presidential candidate Bill Clinton's womanizing in 1991 and 1992.

We're at that stage again.

Presidential campaigns for 2008 and reporters are wondering whether we're about to write new rules about candidates' personal lives and whether their children, their affairs and their divorces are fair game.

This past week's story about a rift between Republican presidential candidate Rudolph Giuliani and his son, rooted in Giuliani's divorce from the son's mother, prompted the speculation. Officials from Giuliani's and John McCain's campaigns asked whether the media will keep children off limits, as they largely have done in recent years.

Bill and Hillary Rodham Clinton asked the media to respect the privacy of their daughter, Chelsea, during their years in the White House. George W. and Laura Bush asked for the same regarding their twin daughters, Jenna and Barbara.

During a break Monday from a Harvard University discussion of the 2008 campaign, the manager of McCain's campaign said he's worried that the rules are changing and candidates' children are at risk of being stalked by television cameras.

"Look at Bush. He set parameters for his daughters. The girls did not want to be involved. For the most part, that was respected," Rick Davis said.

That wasn't the case for McCain's family in 2000. His adopted daughter was subjected to a smear campaign in the South Carolina primary, spread by e-mail.

Davis was asked what difference it would make in the Internet age of blogs for the traditional media to agree to restraint if the information got out anyway.

"The numbers for these blogs are pretty small by themselves," he said. "It's not until it gets picked up that it gets big. If you don't print it, who's going to read it?"

Lots of people, potentially. The Monica Lewinsky scandal broke on a Web site — the Drudge Report — that alone had a big enough following to make it the talk of the nation. Restraint by traditional media would've been pointless after that; Clinton's enemies already were trumpeting the news.

Nevertheless, reporters and their editors should decide in advance how they'll cover the children of candidates this time around.

Giuliani on Tuesday asked the news media to stay away from his family.

"The more privacy I can have for my family, the better we are going to be able to deal with all these difficulties," Giuliani said.