On Mother's Day (May 9), Keith Urban tributed his wife, actor Nicole Kidman, in a social media post celebrating some of the special qualities that she has passed down to their two daughters, 12-year-old Sunday Rose and 10-year-old Faith Margaret.

"Our girls are ALL love, color, kindness and compassion, curiosity and so much more because YOU are all these things...and so much more," the singer wrote on Twitter. "We LOVE you!"

The celebrity husband-and-wife duo of 14 years are known for their frequent, adoring posts celebrating one another and their sweet love story. While they have been fairly private about their family life, Urban and Kidman's two daughters do occasionally make public appearances: Most recently, the two girls virtually attended the 2021 Golden Globe Awards.

However, the couple has opened up about some of the challenging aspects of parenting during the COVID-19 pandemic. In a late 2020 interview with Glamour UK, Kidman explained that one of the most difficult parts of quarantine was watching her daughters grapple with isolation and not be able to see their friends. For her part, she added, her marriage to Urban was a major source of solace: "I am very fortunate to come home to him. My heart goes out to the people who don't have a person to go to now," Kidman noted.

In addition to a thoughtful Mother's Day tribute from her husband, Kidman also shared an image on social media of a bouquet of flowers she received from her daughters' school.

"To all our women out there -- to our mums, our grandmothers, our sisters, our daughters, our aunts, our girlfriends -- I am so deeply grateful to the women who raise other women, who laugh, and love, and grieve, and befriend, and care, and never, ever, ever give up," she wrote. "Happy Mother's Day, and particularly to my Mumma."

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