Shalika Shelton, 30, and her daughter Cartier Jackson were last seen around 3 p.m. on Sunday, June 19 on the 800 block of East Lincoln Highway in Coatesville, local police said.
The girl's godmother and legal guardian told police that Shelton may have taken the child to Philadelphia, police said.
Authorities say Shelton has "untreated mental health concerns."
She was last seen wearing a tie-dye dress and her daughter was last seen wearing a white shirt with a bird on it, jean shorts, and white crocs.
Shelton is known to hang out in South West Philadelphia and Center City, police said.
Anyone with information on the pair's whereabouts is asked to contact the Coatesville Detective Carmen Mollichella at 610-384-2300 Extension 3238.
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