In the latest installment of “Rooted & Restless,” I take a look at two new albums that both grapple with legacy: Steve Earle’s JT, which both mourns the loss of his son and celebrates the body of work he left behind; and Barry Gibb’s Greenfields: The Gibb Brothers Songbook, Vol. 1, which recontextualizes classic songs from The Bee Gees. Both are worth hearing, especially JT. Though tragic in its circumstance, it’s one of the richer, more rewarding Steve Earle albums in recent memory.