Mark Zuckerberg on Thursday revealed that Facebook's first family is growing, with a baby sister on the way for one-year-old daughter Maxima.
"We are all better people because of the strong women in our lives -- sisters, mothers and friends," Zuckerberg said in a post at his Facebook page.
"We can't wait to welcome our new little one and do our best to raise another strong woman."
Zuckerberg's doctor wife, Priscilla Chan, gave birth to daughter "Max" in late November of 2015.
After Max was born, Zuckerberg and his wife said they would give away 99 percent of their Facebook wealth in a philanthropy initiative "to improve the lives of all those coming into this world".
A charitable foundation backed by the couple early this year bought a Canadian artificial intelligence startup as part of a mission to eradicate disease.
Zuckerberg and Chan last year pledged $3 billion over the next decade to help banish or manage all disease, pouring some of the Facebook founder's fortune into innovative research.