“With full and grateful hearts we welcome our beautiful Avery into this incredible world,” Galecki captioned his version of the image, in black and white. “Thank you for all of your love and support. ”
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The couple first announced that they were expecting back in May.
“We are absolutely over the moon to announce that we will soon be welcoming a little one into this crazy and wonderful world,” the couple told PEOPLE. “There truly is love out there for all. We hope ours is the ember of yours, as we feel yours is the ember of ours.”
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Galecki previously said he had been hoping for a girl, explaining on The Talk in May that he’d even painted his nails pink to try and encourage it.
“I get a little bored looking exactly the same way for nine and a half months every year playing Leonard,” he said of his Big Bang character. “So we wrapped and I threw some blue in my hair, then I got superstitious that I was manifesting a boy, when I kind of prefer a girl.”
“Don’t play this tape for my child years from now!” he joked, also noting that he actually valued his baby’s health most of all at the end of the day.
Since announcing the pregnancy, they kept busy documenting how they prepared for baby Avery. Galecki shared a photo in October of the book he was reading, The Expectant Father, with the hashtag “#sundayreading.”
Meyer showed off pictures from her baby shower that same month, where she revealed the name the couple had chosen for their son by displaying large silver balloons to spell “AVERY.”