After almost 25 years of recording music together, the Indigo Girls are not girls. They're women.

After almost 25 years of recording music together, the Indigo Girls are not girls. They're women.

The folk rock duo comprises childhood buddies Amy Ray and Emily Saliers. "Beauty Queen Sister," the pair's 14th studio album, released last month, is a testament to issues of maturity, such as nurturing human-to-higher-power relationships and learning to value home.

Odd, then, that the band's fan base has zero generation gaps? Not if you consider the poetic staying power of their songs. You're much more likely to see lyrics from an IG song on Facebook than a link to the music.

Those messages have made them darlings, heroes even, of the LGBT community, its allies and environmental activists. Concert-goers are likely to identify with these groups, but anyone who digs upbeat Paul Simon-style sounds (who doesn't?) will like IG jams like "Making Promises."