Rebas Son Shelby Blackstock Expecting First Baby!

's son announced on Wednesday that he's about to become a first-time father.

Shelby Blackstock, whom McEntire shares with her ex-husband Narvel Blackstock, revealed in an Instagram post that he and his wife Marissa were expecting their first child.

'Oh, BOY! We’re beyond excited to FINALLY announce our little man is coming in October,' he gushed in the caption, while sharing photos of himself and Marissa beaming at Disney World as they posed in front of Cinderella's Castle at the Magic Kingdom.

Shelby shared his happy news just eight months after the — who was the ex-husband and former manager of — after a years-long battle with skin .

The lovebirds shared a sweet kiss with the castle towering over them and held up a cute Disney-themed onesie with a baby Mickey Mouse embroidered on the front. 

It featured their family name, along with the baby's due date of October 2026. 

'See ya real soon, pal! Mommy + Daddy love you! 🤘🏻,' Blackstock signed off in a sweet message to his future son. 

He and his wife beamed in another photo as they strolled down the bridge to the castle while holding hands, as Marissa rested her free hand over her burgeoning baby bump. 

They shared a loving kiss in another snap taken in the shade of the castle while both held up a corner of their sonogram for the camera, and Shelby stood behind his wife and placed both their hands over her stomach in a subsequent shot.

Blackstock revealed a custom embroidered Mickey ears hat and a Disney-branded sippy cut commemorating his son's upcoming birth; pictured with McEntire in 2011 in Nashville