There are a number of things about the story that lend credence to the speculation, the picture at the linked article being one. Another is the fact that she allegedly broke her water in Texas and flew to Alaska to have the baby, rather than have it in Texas, like any normal person would do. She would have to be in Alaska during the time of the birth, of course, and it is possible she was notified while at the conference that her daughter was about to have the baby.
All of this is totally wild speculation at this point, but so much fun.
Update: I figured it was too good to be true.