Lindsay Lohan celebrated her 27th birthday at Cliffside Rehab Centre in California today (04.07.13).

The 'Mean Girls' actress is completing a court ordered 90-day-stint in rehab and while she ''didn't like'' marking her birthday in the centre she ''made the most of it'' by sharing cake and ice-cream with patients and her lawyer, Shawn Holley.

Visiting day at the clinic is Sunday, when friends will reportedly hold a belated birthday celebration for the actress.

A source told RadarOnline.com: ''Lindsay seems to be in a very good place, and is responding very well to treatment at Cliffside.''

Lindsay still about halfway through her sentence with the insider adding: ''She is scheduled to be released at the beginning of August.''

Lindsay will be kept busy following her release from rehab by the premiere of her movie, 'The Canyons', after co-star Tenille Houston said schedules had been changed to accommodate the star.

He explained: ''We were originally going to have the premiere in June but it got switched around so Lindsay could be there. And we're going to be in the Venice Film Festival also and I'm going and so is Lindsay.''

The Canyons will be released from August this summer.