The 'Heartbeat Song' singer was pictured planting a kiss on her other half while sitting in the audience at the star-studded event on Saturday, 28 March.
Kelly was among the performers at the annual gala held in honour of Muhammad Ali. This year it also recognised Kelly's mother-in-law Reba McEntire's birthday.
She married Reba's stepson Brandon in 2013, and they are parents to daughter River Rose, born June 2014.
It was a busy weekend for Kelly.
After performing at Celebrity Fight Night, she headed over to Los Angeles to appear at the iHeart Radio Music Awards 2015, where she also took to the stage.
Her current single 'Heartbeat Song' is taken from her seventh studio album Piece by Piece. It reached the Top 10 in the UK charts on release.