Where'd the time go? Obama girls now young women

And Bill and Hillary Rodham Clinton were extremely protective of Chelsea, who entered the White House at an awkward stage. Her parents were furious when Mike Myers referred to their daughter in an insulting way on "Saturday Night Live"; the comic later apologized.

Whereas many White House children seem to suffer some sort of embarrassment or scandal, the Obama girls have had none, not even a bad hair day, it seems.

"Compared to other White House families, this is clearly the most functional," says Wead, ho chronicles a host of misfortunes of White House kids in his book, "All the President's Children." ''This has been one of the most successful stories."

Clearly one reason is that the Obamas spend so much time with their kids. The president has coached their teams, and faithfully attends games and parent-teacher conferences. The first family is known to have dinner together in the White House most nights; Michelle Obama in her convention speech evoked the image of the family "strategizing about middle-school friendships."

That will likely help the president avoid the guilt that, Wead says, overcame Ulysses S. Grant on the occasion of his daughter's White House wedding. She left on her honeymoon, and Wead says the president then collapsed on her bed and wept.

"He had been so busy as president that he felt he had missed her life," Wead says. "It all had happened too fast for him."