On Feb. 11, Akins announced the arrival of their new bundle of joy on social media, calling Lennon their "early Valentine baby."
"Her sisters couldn't be happier to finally get to kiss her little face," Akins wrote, sharing that their daughter weighs 9 lbs. and 2 oz. and has dark hair and blue eyes.
Rhett and his wife are already the parents of two girls: Willa Gray and Ada James. The couple married in 2012 after being childhood friends.
Last summer, the couple announced that they were expecting another baby.
"We decided we didn't have enough princess dresses around the house so we're adding another Akins baby girl to the family early next year," Lauren Akins wrote last year. "We are absolutely over the moon for our baby girl! Our girls cannot wait to meet their little sister."
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Rhett's family life is a frequent subject of his songs. Last year, Rhett shared the video for "Remember You Young," which features home videos of his daughters.