The "Pacific Rim" star also shared a glimpse at the newborn baby in a photo attached to the post. The black-and-white snap shows baby Winston's small hand holding his daddy's finger. In addition to Winston, the British actor is a father to a daughter Isan from his previous marriage to Dormowa Sherman.
Elba and his make-up artist girlfriend confirmed that they were in relationship last year, around the same time they announced the baby news. "Idris and Naiyana are so in love and this is the icing on the cake for them," a source told U.K.'s Mirror back then.
"They had been keeping it quiet as it's early in the pregnancy, but they've told family and friends and Naiyana is beginning to show. She is absolutely lovely and she's looking radiant. Her and Idris are a great couple and feel lucky to have found each other," the source added. "Obviously Idris is a bit of a TV heartthrob so Naiyana is the envy of women across the country. But the truth is Idris is the one who really considers himself the lucky one. He's a great dad and she'll be a brilliant mum. They can't wait for their new arrival."