Supreme Court Justice Ruth Bader Ginsburg on Monday made her first appearance in public since surgery in December to remove cancerous nodules found in her lungs.

Ginsburg attended a performance about her own life called “Notorious RBG in Song” at the National Museum of Women in the Arts in Washington, D.C., keeping a low profile at the event. The performance was given by Ginsburg’s daughter-in-law Patrice Michaels, a soprano who created the program, according to the Washington Post.

Ginsburg remained in the back of the crowd during the event. No mention of her attendance was made during the performance.

Ginsburg received surgery on Dec. 21 to remove two cancerous nodules from her left lung, a procedure that usually requires a six- to eight-week recovery. As a result, Ginsburg missed a round of oral arguments last month — marking the first time ever the justice had done so.

Her most recent surgery marked her third bout with cancer and sparked speculation about her health and future on the Supreme Court.

However, Chief Justice John Roberts said Ginsburg would continue to participate in the consideration of cases by reading briefs and argument transcripts, and she has done some work from home related to deciding which cases the court would put on the docket.

The Supreme Court announced last month that Ginsburg had no remaining signs of cancer and no additional treatment would be necessary.

Ginsburg, 85, is the oldest sitting Supreme Court justice. She previously battled pancreatic and colon cancer.