Facebook CEO Mark Zuckerberg and his wife Priscilla Chan just announced the birth of their second baby girl.
"Priscilla and I are so happy to welcome our daughter August! We wrote her a letter about the world we hope she grows up in, and also hoping she doesn't grow up too fast," Zuckerberg wrote on his Facebook page on Monday.
The couple wrote a similar letter to their oldest daughter, Max, when she was born in 2015. In Max's letter, however, Chan and Zuckerberg focused on the world they hope to see her grow up in. But for August, they focused more on childhood.
"Childhood is magical. You only get to be a child once, so don't spend it worrying too much about the future," they wrote. "You've got us for that, and we'll do everything we possibly can to make sure the world is a better place for you and all children in your generation."
The couple announced they were expecting another little one in a Facebook post in March.
The Associated Press contributed to this report.