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, 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 wrote.

Mom and dad came and saw us with @neilyoung the other day..nothing better than all being together in one place! #family

Posted by Lukas Nelson & Promise Of The Real on  Wednesday, October 14, 2015

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 were still getting details on Willies 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 in Reading, Pa., are available while Friday's show in Roanoke, Va., is rescheduled for Monday. Original tickets will be honored for the new dates.

You think you know Willie Nelson?