After Willie Nelson was forced to cancel several tour dates with Merle Haggard earlier this week, fans have been worried about the singer's health.

Nelson's son, Lukas, is putting those worries to ease, revealing more about his father's 'medical issue' with two photos on Facebook. In one, Willie joins him on his tour bus at a recent tour stop while Lukas' band Promise of the Real is opening for Neil Young.

On Wednesday (Oct. 14), Lukas thanked fans for their prayers and gave some insight into his father's condition. "Thanks for the prayers and love for dad, his health issue is minor and he's doing great, love to all..." he writes.

Fear for Nelson's health arose after he canceled one show of the Django and Jimmie Tour and rescheduled two more due to his illness. His tour with Haggard was scheduled to kick off Thursday at the Florence Civic Center in Florence, S.C. That show has since been rescheduled for April 6, 2016.

"This is all news to us at the moment and we’re still getting details on Willie’s medical concern," Nick Hooker, Senior Marketing Manager for the venue, says. "We’ve been told this is not life-threatening, but will require several weeks to fully recover. We will keep you updated as more information comes to light."

Currently, refunds for Nelson's concert on Saturday (Oct. 19) in Reading, Pa., are available while Friday's (Oct. 16) show in Roanoke, Va., is rescheduled for Monday (Oct. 19). Original tickets will be honored for the new dates.

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