Jessica Simpson (left) and Ashlee Wentz
Denise Truscello/WireImage
"They're going to have to. It's already developing really quick," Jessica said Monday at a taping of the The Ellen DeGeneres Show.
Ashlee – described by husband Pete Wentz more than two weeks ago as due at any moment – has already tried other ways to begin labor.
"Different foot massages and stuff," Jessica told DeGeneres in the show airing Wednesday. "I don't know. I think she's really just jumping around trying everything right now."
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