The American Idol alum, 29, was glowing in a green maternity dress at the event.
“#CMTAOTY,” she Instagrammed an image with her husband backstage.
While onstage, Aldean, 40, shared a somber statement, reflecting back on the Route 91 Harvest Festival, the outdoor country music concert where he was performing before a gunman killed 58 people and injured 489.
“We’ve been tested beyond our worst nightmares the past few months. Heartbroken doesn’t even begin to explain how some of us feel,” he said. “But we have proven time and again in this country that we have the power to overcome anything that threatens our way of life or our freedom. We dedicate this night to you and to everyone who’s experienced loss or tragedy in the past few months. Like Keith said, we will get through this together,”
Kerr and Aldean — who radiated the red carpet at the ACM Honors in August — expect their first child together.
Aldean is already dad to daughters – Kendyl, 9, and Keeley, 14 – from his previous marriage to Jessica Ussery.