Gabriella McWilliams left her group home on May 18, Lumberton Township police said.
There have been several unconfirmed sightings of her in other parts of Burlington County including Pemberton and Shamong townships, police said.
Gabby is 5-foot-5 and about 125 pounds with brown hair.
She goes to Hampton Academy in Mount Holly, which educates students with social, emotional, academic or behavioral challenges, according to her mother and police.
Anyone who may know her whereabouts is urged to call Lumberton police at 609-267-8300.
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