The Die Hard star is a proud dad to baby daughter Evelyn Penn, who was born in Los Angeles on Monday, 5 May.
A rep told E! News that both Evelyn and Emma are "healthy and doing beautifully", adding the tot weighed in at 8lbs 10oz.
Bruce and Emma are also parents to daughter Mabel Ray, two.
In addition to his daughters with Emma, Bruce is dad to three girls from his marriage to ex-wife Demi Moore: Rumer, Tallulah and Scout.
59-year-old action star Bruce has often spoken in interviews about how much he loves fatherhood - and the happiness Emma has brought to his life.
"She's brought me her incredible spirit and class and beauty and love," he told Zoomer. "Before I met Emma, I was very pessimistic about finding that special woman whom I would want to spend my life with.
"I thought it would be difficult for someone like me who is well known to find a woman who didn't have an agenda and just wanted to be with me because they loved me, pure and simple. With Emma, I knew I had found a woman who didn't need or want anything from me other than for us to be together and be happy."
Congrats to Emma and Bruce!
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