Abby Lee Miller has more than one reason to celebrate!

The reality star rang in her 52nd birthday on Monday with a luncheon at Buca di Beppo in Los Angeles, just weeks after leaving her rehabilitation facility.

Along with a handful of close friends and family, a group of Miller’s Dance Moms students (including JoJo Siwa and her mother, Jessalyn Siwa) attended the party.

Of course, Miller documented the party on social media, posting several photos with her friends on Instagram. In one photo, she joked about her tan while posing with Siwa and singer Mackenzie Sol.

“I was showing off my summer tan, posing with the 2 fairest people in Cali!!! Which 1 of us is “the fairest of them all”???” she captioned the above shot.

In another shot, she thanked her friends for “sharing in my celebration.”

And of course, the day wouldn’t be complete without birthday cake. Miller posted a photo of her elaborate, two-tiered cake featuring a champagne glass with Barbie legs sticking out the top.

Miller left her rehabilitation facility in September. In April, one day after undergoing emergency surgery for what was initially thought to be a spinal infection, the reality star — who was released from prison in March — was preliminarily diagnosed with non-Hodgkin’s lymphoma, a cancer that develops in the lymphatic system.

“It was not an infection, it was a type of a non-Hodgkin’s lymphoma — it’s a type of a cancer,” said Dr. Hooman M. Melamed, an orthopedic spine surgeon at Cedar Sinai Marina Del Rey Hospital who treated the star. “We’re getting an oncologist involved and we have to figure out what the next steps are as far as chemotherapy or radiation or more spine surgery. Depending on the tumor type, depending on the sensitivity of the tumor — it just depends the type but I feel more than yes, she will undergo chemotherapy or radiation.”

The doctor added that it was a “preliminary diagnosis pending pathology and oncology results.”

Miller went into the emergency room after she experienced “excruciating neck pain” and weakness in her arm, and after her condition deteriorated over the next couple days, Dr. Melamed performed emergency surgery for a multi-level laminectomy.

“If we didn’t do something, she was going to die,” Dr. Melamed told PEOPLE. “Her blood pressure was bottoming out. She was not doing well.”

Since her diagnosis, the former Dance Moms star has been receiving chemotherapy and documenting her journey via social media.

Miller had been living in a halfway house since serving her 366-day sentence for bankruptcy fraud at the Victorville Federal Correctional Institution in California, which she entered in July.

In May, Miller was officially released from the halfway house.