In keeping with the Batman theme, the Grammy winner, 30, was sporting a black dress and black boots, with a black clutch. Earlier in the evening, she posted a photo to Twitter, "channeling my inner Cat Woman" before the show.
On the carpet, she and Cibrian, 39, firmly held hands as they posed for photos with Mason, 9, and Jake, 5.
Courtesy Leann Rimes
All four had mustaches inked on their index fingers, and at one point they posed for photos laughing and holding up their fingers to their noses.
Rimes checked into treatment at the end of August, but took a break to uphold her commitment to perform some concerts in the Midwest. She has a number of shows scheduled for the next three months, beginning with a swing through New England in October.
Reporting by REAGAN ALEXANDER