Fashion maven Rachel Zoe is turning her back on her career — and her superskinny frame — to concentrate on giving son Skyler, 17 months, a sibling, Star magazine is reporting.

"Rachel wants a new baby badly and is making it her No. 1 priority for a while," a source tells Star. "They've been trying for months, but it hasn't happened yet — so she's making some changes, starting with her body. Friends say she's kidding herself if she thinks she can get pregnant while weighing 90 lbs."