PHILADELPHIA -- Police said a 3-week-old baby boy missing from his grandmother's house Saturday night along with a 15-year-old female cousin was found safe Sunday afternoon.

The infant was apparently taken from the home on the 3000 block of North Sydenham Street at about 8:30 p.m., police said.

According to authorities, 15-year-old Alicia Barham, who lives in the Sydenham Street home, wanted to take the baby for a walk in her old neighborhood, which is the 1800 block of Bouvier Street.

The grandmother said no, but police allege that Barham took the child -- identified as Tamir Johnson, of the 3700 block of North 16th Street -- and left.

After missing all night and through the morning, Barham turned up with the baby at her mother's house on the 1400 block of Marshall Street at about 2:30 p.m., police said.

It wasn't immidiately clear where Barham took the infant all night, said special victims detectives, who were waiting for the grandmother's permission to question Barham.