Sierra Dawn Hull is an American bluegrass singer, mandolinist, and guitarist. Hull was signed to Rounder Records at the age of 13 and released her debut vocal album, Secrets, in 2008 at the age of 16. A good chunk of popular music’s real estate has been carved up along lines of age these last half-dozen decades, and we’re used to seeing young musicians aim exclusively for young audiences then flounder as they outgrow teenaged listeners’ tastes and concerns.