Lamar Odom has reportedly checked out of rehab after doing a one-day stint. According to several reports, the NBA player didn't tell his wife Khloe Kardashian or his family that he was seeking help for his alleged cocaine addiction.

A family source told Hollywood Life that everyone is "worried sick" about Odom.

"We hope he's all right but like Khloe and the rest of his family, [as far as we know] he's a gone ghost," the family member said. "We're all worried sick because it's been at least a day and a half and he hasn't called us."

"Khloe doesn't know where he is, he's just gone," the family member continued. "We hope he really is in rehab but if he's not we worry he's doing something dangerous to himself. The last thing we want to hear is a detective calling telling us the worst news in the world."

Odom reportedly checked into rehab on Sept. 4 after getting an ultimatum from his wife. According to TMZ, Kardashian told him to either get help or the marriage was over.

Since leaving the facility everyone has been wondering where Odom has disappeared to. According to Hollywood Life, he has been hiding out in a luxury apartment in The Roosevelt Lofts in downtown Los Angeles - the same building where he reportedly would go to for his alleged "crack binges" and parties.

"Lamar is currently holed up at The Roosevelt Lofts in downtown LA," the source said. "Lamar went to lunch at Octopus Japanese restaurant today at 12:30 p.m. and then straight back to his apartment."

Odom was spotted having lunch with a friend at the sushi restaurant but barely touched his food, TMZ reports. The wait staff didn't have much to say about the athlete but said he was "nice enough" and did leave a pretty nice tip.