Caleb Followill is to become a father for the first time.
No other details about the pregnancy have been revealed although it is thought Lily is in her second trimester.
Caleb and Lily tied the knot in May after dating for more than two years and the Victoria's Secret beauty recently said she was loving every moment of married life.
She said: "Married life is the best. I'm so proud to be a wife."
Lily - who walked down the aisle in a custom-made Vera Wang gown - also admitted her wedding was perfect and says she wouldn't have changed anything about the sunset ceremony.
She added: "It was really an amazing day. It was more beautiful than I could've imagined."