Lil Wayne will be completely "focused" once he leaves prison.
The rapper - real name Dwayne Carter - is currently serving a one-year jail sentence in Arizona on a gun charge but fellow musician Fat Joe says he will be a changed man once he's released.
He said: "He's a beautiful dude. He did what he did. He had a gun on him, but people don't really know how much of a great father that he is, the great person he is, a friend, a loyal dude. He's charismatic. It's just sad to see him over there like that, but I'm pretty sure he learned his lesson and he's gonna be focused."
Fat Joe also admits the 'Lollipop' hitmaker isn't letting his jail time get him down.
He told MTV: "He's in great spirits. I love Lil Wayne; that's like my little brother. He's just the coolest dude on Earth. I tell you one thing, him not being high made me realise how much funnier he is. This guy has jokes. We were up in there for four hours, just telling jokes, dying laughing, falling on the floor."
When he is released from prison, Lil Wayne will start a three-year probation period on an unrelated drug possession charge.
He was arrested in 2008 when police at a US Border Patrol checkpoint found an ounce of cocaine, 41 grams of ecstasy, four ounces of marijuana and a 40-calibre pistol on board the star's tour bus.
He avoided facing charges of possession of a narcotic drug for sale, misconduct involving weapons and possession of drug paraphernalia by pleading guilty to one count of possession of a dangerous drug on June 18.