What is soul sister?

"Soul Sister" is a popular song by the American rock band Train. It was released as a single in 2009 and is part of their fifth studio album, "Save Me, San Francisco." The song became one of the band's most successful hits, reaching the top 10 in several countries and winning a Grammy Award for Best Pop Performance by a Duo or Group with Vocals in 2011.

The song's catchy melody and feel-good lyrics are centered around themes of love and admiration. Its upbeat and folk-pop style contributed to its widespread appeal on both pop radio and adult contemporary stations. Over the years, "Hey, Soul Sister" has been featured in numerous commercials, TV shows, and movies, further cementing its status as a staple of Train's discography.