Rehab dropout Lindsay Lohan

Lindsay Lohan is "doing great" in rehab, says her mother Dina.The 'Mean Girls' actress, who checked into Malibu's Promises rehab center in May, is in regular contact with her family.Dina told People magazine: "I talk to her every day. She's going to do Promises' extended care program."The program, which includes group therapy, is designed to help patients"make the transition from residential alcohol or drug rehab treatment back into their community". Dina also revealed she and the rest of the family are planning to travel to Los Angeles to celebrate Lindsay's 21st birthday on July 2. Earlier this month, Lindsay cancelled her birthday party at Las Vegas' PURE nightclub.Lindsay's security guard has revealed the star isn't planning to spend the landmark birthday in rehab.Ty Dux said: "It won't be on the Promises premises."Lindsay, 20, entered rehab for the second time this year following her arrest for DUI (driving under the influence) in May. Police found a "usable amount" of cocaine in the vehicle Lindsay has been driving.