Mark Zuckerberg and Priscilla Chan have welcomed their first child, announcing the news in a touching Facebook post this evening. The couple are new parents to a baby girl Max, with the pair sharing a snapshot of their new family unit to the Facebook founder’s public profile. As well as introducing Max to the online world, Zuckerberg announced that he and his wife have decided to donate 99% of their Facebook shares – currently valued at $45billion – to good causes in an aim to make the world a better place. In the message shared to Facebook, the pair aim that “during our lives to join many others in improving this world for the next generation.” The couple also wrote an open letter to their daughter – where they told their little girl: ‘Your mother and I don't yet have the words to describe the hope you give us for the future. Your new life is full of promise, and we hope you will be happy and healthy so you can explore it fully. You've already given us a reason to reflect on the world we hope you live in.’ The billionaire entrepreneur previously wrote about his expectations of being a father, posting: “You feel so hopeful when you learn you're going to have a child. "You start imagining who they'll become and dreaming of hopes for their future. You start making plans, and then they're gone. "It's a lonely experience." Priscilla and Mark were college sweethearts and dated for 9 years before tying the knot in 2012.