Here's what Facebook CEO Zuckerberg said to his newborn daughter!

San Francisco: Facebook CEO Mark Zuckerberg and his wife Priscilla Chan have been blessed with second child - a baby girl, on Monday.

While the proud daddy was posting the photo of his daughter christened August, he looked at her and said, "I am optimist about your generation and the future."

"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," he posted on his Facebook page.

In the letter to her new-born daughter, Zuckerberg said, "Dear August, Welcome to the world! Your mom and I are so excited to see who you will become."

"When your sister was born, we wrote a letter about the world we hoped she and now you will grow up in -- a world with better education, fewer diseases, stronger communities, and greater equality. We wrote that with all the advances in science and technology, your generation should live dramatically better lives than ours, and we have a responsibility to do our part to make that happen. Even though headlines often focus on what's wrong, we still believe these positive trends will win out," he said.

He said rather than write about growing up, they want to talk about childhood. "The world can be a serious place. That's why it's important to make time to go outside and play."

"You will be busy when you're older, so I hope you take time to smell all the flowers and put all the leaves you want in your bucket now. I hope you read your favorite Dr Seuss books so many times you start inventing your own stories about the Vipper of Vipp."

"Childhood is magical. You only get to be a child once, so don't spend it worrying too much about the future. 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."

"August, we love you so much and we're so excited to go on this adventure with you. We wish you a life of joy, love and the same hope you give us," he said.

When Maxima Chan Zuckerberg ("Max") - Zuckerberg's elder daughter -- was born in 2015, he shared a letter and announced the creation of the Chan-Zuckerberg Initiative.

According to Mashable, Zuckerberg revealed earlier this month he would be taking two months paternity leave this year.

Facebook allows employees to take four months off. Zuckerberg will be taking a month off now and another month off later this year.