Aaron Carter may have already been dead at the time of his scheduled rehab therapy session on Friday, November 4. The late teen pop icon missed his scheduled appointment less than 24 hours before his body was discovered unresponsive in his bathtub on Saturday morning, November 5, according to a news publication. Carter had been readmitted into the rehab program one week prior to his devastating death after he stepped away from sessions for a short period of time. ‘PLEASE DON’T DO THIS TO YOURSELF’: AARON CARTER’S FIANCÉE, MELANIE MARTIN, BEGGED HIM TO STOP DRUG USE DAYS BEFORE HIS DEATH By the…