A mother’s mournful prayer that cops catch her daughter’s killer before the teenager — slain in a drive-by shooting in East Harlem — was laid to rest yesterday was answered, a friend said.

At the funeral of Cheyenne Baez, 17, at the Bethel Gospel Assembly in East Harlem, a church elder announced that Boris Brown, 20, had been picked up for the fatal spray of gunfire on Oct. 3.

Baez’s mom, Lisa, was told on Tuesday. The suspect had been picked out of a lineup.