New Castle County Police say Darlene Cooper and her daughter Sonay Fogan both live on the 700 block of Christiana Road in the Cedar Wood Apartments complex.
Cooper and the infant were reported missing on Sunday by Cooper's mother who said they were last seen on Saturday by a relative at a motel with Cooper's boyfriend.
The mother says she also got a text from her daughter that day that they were headed to an unknown location in Philadelphia.
Cooper is black, 5'2", 160 pounds with brown hair and brown eyes.
Police say her medical status gives reason for concern about her disappearance.
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