"Reese's husband Jim hasn't left her side and he doesn't plan to."
This will be the first child for Reese's hubby, Jim Toth, and the source says he's nervous about Reese going into an early labor.
"Jim is really worried about the baby. He's a first-time father so this is all really new to him and he just wants everything to be okay," the source revealed.
"He's a bundle of nerves. Meanwhile, this will be Reese's third child, so she's been through this before and she's trying to keep him calm."
As RadarOnline.com was first to report, Reese, 36, was taken to a Los Angeles hospital on Tuesday evening, stemming from complications with her pregnancy. She was released that night, and then taken to the hospital again on Wednesday.
"Unless she goes into labor, Reese will remain in the hospital under the watchful eye of the doctors," the source said.
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