No Siblings, No Presidency

According to an unimpeachable source -- trivia printed on the wrapper of some little swiss-cheese things we just ate -- there has never been an "only child" U.S. president. This seems like a good way to weed out candidates right now and save everybody a lot of time and trouble.
Are there any Only Children running or probably running in 2008? We investigate, after the jump.
Of course, there has never been a black president or lady president or Mormon president or president who can't raise his arms or president named "Hussein," either, so the Only Child rule may not be particularly relevant this time around.
Nonetheless, we like dumb gimmicks and pointless lists as much as anybody, so here goes:
*Barack Obama: Five brothers and a sister, allborn and raised in Kenya. Of course, they are half siblings, but we figure Bill Clinton's brother is a half-sibling, too -- whether or not that's true.
*Hillary Clinton: The lady's got two natural-born brothers, Hugh and Tony. Better yet for Hillary's presidential aspirations, at least one is a crooked loser andpublic embarrassment.
*Mitt Romney: He's a Mormon with theMagic Underwear, so he's got like a hundred siblings and probably three or four (white) wives.
*John McCain: WALNUTS has a brother and a sister, Joe and Sandy. Also, John McCain is divorced and probably not really American since he was born in Panama.
*Tommy Thompson: It's looking better for"Tommy Gun," because his crazy brother Allen "Ed" Thompson has beenrepeatedly charged with felonies!
*Duncan Hunter: Reportedly hasunspecified siblings.
*Tom V For Vendetta Vilsack: Orphaned at birth, likeJesusMoses. But he may have a secret sibling out there somewhere. If not, his loss will be even greater than previously predicted.
*Evan Bayh: We can't findany mention of brothers or sisters, and he's the spoiled brat in the photo, so he better withdraw now or provide proof of siblings. (UPDATE: He's got a half-brother. And we've got Evan Fever!)
*John Edwards: Yes! He's got awacky drunken brother who always gets arrested! Wesley Blake Edwards could be this nation's next Billy Carter and Roger Clinton combined !
*Rudy Giuliani: He's finished. The twice-divorced gay-roommate-having opera-loving Manhattan dandyis an only child.
*Joe Biden: Who fucking cares?
We left out a few also-rans like Sam "Brokeback" Brownback, because this turned out to be much more difficult than we imagined. And no wonder -- most of the 2008 siblings we know about are buffoons and minor criminals.