The Rosemary's Baby actress announced that she had met her tenth grandchild by posting a picture of the newborn in hospital on Twitter, with the caption, "I have a new granddaughter. I have a new granddaughter!!!"

This is the first child for 30-year-old Dylan and her husband. She revealed she was expecting a girl when she arrived on the red carpet of TIME’s 100 Gala in April (16) with a blossoming bump.

“I picked a name, but my husband would kill me if I told you,” Dylan told People at the event at the time. “He wants it to be a secret."

Mia, 71, added, “I have nine grandchildren, but I’m excited about this one... So is her husband.”

Dylan famously made headlines in 2014 when she wrote a piece in the New York Times newspaper accusing her adoptive father, director Woody Allen, of sexually abusing her when she was a young girl. Woody has always denied the allegations and has never been charged.

Dylan's brother Ronan recently spoke out to support his sister in May (16), admitting he regrets telling her to stay silent on the alleged assault.

"Initially, I begged my sister not to go public again and to avoid speaking to reporters about it," he said to The Hollywood Reporter. "I'm ashamed of that, too. With sexual assault, anything's easier than facing it in full, saying all of it, facing all of the consequences...

"I ultimately knew she was right. I began to speak about her more openly, particularly on social media. And I began to look carefully at my own decisions in covering sexual assault stories."