Mark Zuckerberg and Priscilla Chan expecting third child

Facebook founder took to Instagram on Wednesday to announce that he and his wife had baby number three on the way.

He also revealed that the baby would be another girl. 

Priscilla's stomach, Mark wrote, "Lots of love. 

Happy to share that Max and August are getting a new baby sister next year!" 

Mark and Priscilla currently share two daughters - Maxima, six, and August, five. 

The couple began dating in college in 2003 and married in 2012. 

When they celebrated their 10th wedding anniversary in May, Mark wrote on Facebook, "10 years married and half our lives together. Here's to more adventures."