Brooke Mueller is in grave danger of losing her parental rights of her twins with actor Charlie Sheen, Breaking Celebrity News has learned.

Social workers have determined that the troubled socialite ditched the sober living facility where she was seeking treatment and is now renting a nearby beach cottage in San Clemente, Calif., so her boyfriend can visit, a source revealed.

Mueller, 35, has temporarily lost custody of Bob and Max, four, while attempting to get clean. Sheen's second wife, Denise Richards, was granted temporary guardianship of the boys while she entered rehab for the 20th time.