Ivanka Trump is expecting her first child with husband Jared Kushner.
"I have been wanting to share some amazing news with you all for some time... I'm pregnant! Jared and I couldn't be more excited," she tweeted on Friday.
This will be Donald Trump's third grandchild; his oldest child, Donald Trump Jr., has a son and a daughter.
Ivanka, 29, also used Twitter to announce her engagement.
She and Jared, 30, were married in an Orthodox Jewish ceremony in 2009.
Ivanka is a vice president in her father's real estate company and Jared is the owner of The New York Observer.