What happens when you put Brad Paisley, Tim McGraw, Darius Rucker and Jimmie Allen in a room together? According a post from Paisley's Instagram account, it culminated in a late-night jam session for the ages.

In a video posted on Feb. 13, Paisley is shown sitting in a circle with the three fellow country stars, guitars in hand. The foursome roll through a version of "Family Tradition," the 1979 hit single from Hank Williams Jr., which readers can watch above.

The pals showed off some impressive harmonization during the song's roaring chorus. It's unclear how the hangout happened, but it's clear that they all had a great time: McGraw also shared the video on his Instagram account, adding the caption, "Great hangin' with these guys the other night. As usual Paisley’s guitar has to be the loudest in the room."

Rucker later replied to McGraw's post with the message, "Great night, man. Feels like a new #familytradition to me! Good times."

In the video's description, Paisley shares that viewers can see a decanter shaped in the likeness of Williams Jr., which was once owned by the late Little Jimmy Dickens. ("It's empty," he admits.) "Also, [the] leg lamp in the background" -- a nod to the classic 1983 film A Christmas Story in which a version of the lamp is featured -- "is a major award," he writes.

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