Troubled rapper Chief Keef is heading back behind bars for a probation violation, just 13 days after he was released. The 18 year old, real name Keith Cozart, is heading to a rehabilitation facility associated with the Cook County Department of Corrections, after a Chicago, Illinois judge sentenced him to 90 days for failing a random drug test. Keef took to Twitter.com on Wednesday (06Nov13) to tell his followers he was returning to jail and wrote, "Judge Putting me Back in jail See y'all later." Keef's random drug tests stem from a May (13) arrest for speeding, for which he pleaded guilty and was ordered to undergo regular testing as part of his sentence. In September (13), he failed by testing positive for marijuana, and began a 20-day sentence in jail on 15 October (13). However, he was released 11 days early on 23 October (13), after receiving credit for good behaviour. It was the 18 year old's latest run-in with the law - he already has a 2011 firearms conviction on his record, and he is currently facing two claims for child support from two different women.