Famed Canadian musician Joni Mitchell held a show this week in the United States, almost 20 years after her last live concert. The 78-year-old artist sang and played guitar Sunday at the Newport Folk Festival in the American state of Rhode Island. Seated much of the time, Mitchell performed with a crowd of other well-known musicians, including American singer-songwriter Brandi Carlile. It was Mitchell's first appearance at the Newport festival since 1969. The highly-awarded singer-songwriter has struggled with health problems since suffering from an aneurysm in 2015. The condition caused bleeding in her brain. Mitchell temporarily lost her ability to speak, walk and play guitar. Her last full show was in late 2002, but she has appeared at special events since then. Her 75th birthday was the center of a celebration in Los Angeles. She was an honoree at the 44th Kennedy Center Honors for lifetime artistic achievement in December last year. Speaking before the Honors ceremony, Brandi Carlile said of Mitchell, “She changed my life… She invented the confessional singer songwriter. She invented a job for me.” This was, Carlile explained, similar to the "Joni Jam" musical gatherings that have brought famous friends like Elton John to Mitchell's Los Angeles home in recent years. And Mitchell did not just sing. Halfway through the performance, she played an electric guitar. It was her first time playing guitar in public since her aneurysm, Carlile said. In an interview with CBS News, Mitchell said she had re-learned how to play guitar by watching videos online.