The woman who was stabbed more than 20 times and found in the Queens attic of a cop’s brother who hanged himself weeks earlier had been missing since December, her distraught family said yesterday.

Samantha Bermudez, 19, vanished while walking to her sister’s apartment Dec. 7 in upper Manhattan.

Her mother, Evelyn Nunez, 51, immediately started putting up fliers near their home.

“I spent 10 months looking for my daughter day and night,” Nunez said last night at a memorial service at a Harlem funeral home.

Bermudez’s body was found on Aug. 4 when Devendra Autar’s cop brother, Devchand, was cleaning up Devendra’s belongings and detected a horrific smell from the attic.

When Devendra Autar committed suicide, he wrote in his note, “I’m going to hell for what I did.”