Baby Bieber has arrived! Justin and Hailey Bieber welcomed their first child into the world, the former revealed on Instagram on Friday, August 23. “Welcome home Jack Blues Bieber,” the singer wrote alongside a photo of the little one’s feet and Hailey’s nail. The pair first announced they were expecting in May via a social media video that showed them renewing their vows. In the romantic clip, the model flaunted her growing baby bump in a lacy white gown. In the mom-of-one’s July interview with W Magazine, she revealed she was at the end of the second trimester when they publicized their exci…