Toby Keith opened the doors to his Oklahoma property to PEOPLE Country for a cover story in September ... he says), and with his new album Bullets in the Gun, due in October, he'll have more ...

Funds raised from the "Should've Been a Cowboy" cover will go toward the Toby Keith Foundation ... happens to be the name of ...

The album of the same name was widely successful, selling 3.1 million copies. Was Toby Keith in the military ... Diana Leyva covers trending news and service for The Tennessean.

But it's the inclusion of Toby Keith that's the most poignant. His appearance on "Ships That Don't Come In," with Luke Combs, is his final studio performance before his death in February.

Six months after Toby Keith's untimely death ... featuring 17 duets of Diffie classics in March. The tribute album featured ...