“We are so thankful for all the prayers and support and are excited to take some time together as a new family,” the couple said in a statement to Us.

After two years of dating, Nettles and entrepreneur Miller tied the knot in a small Tennessee ceremony in November 2011. The couple announced they were expecting their first child together in June, and Nettles proudly showed off her baby bump during a Sugarland concert in July.

“They are thrilled beyond belief,” Sugarland’s manager, Gail Gellman, tells PEOPLE.

The Grammy winner, 37, is due in November, Gellman says, which will coincide with the couple’s first anniversary since their sunset wedding ceremony outside Nashville, in which Nettles dazzled in an Alexander McQueen gown at a chapel nestled in the foothills of the Smoky Mountains.