This Grey’s Anatomy star has been hiding some exciting baby news!

Actress Ellen Pompeo has become a mum for the second time – but she managed to keep her new arrival a secret from the media for two whole months!

The Grey's Anatomy lead revealed on social media last night that her daughter Sienna May Ivery had been born in August by surrogate. She already has one child, five-year-old Stella Luna.

Ellen thanked her co-stars for their help in keeping Sienna's arrival under wraps:

The star also shared a beautiful picture of her husband Chris Ivery kissing the new little one.

The black-and-white photo was captioned, "We love you more than words can say."

We know the baby's a cutie, but it's this amazing nursery we can't get over – is it possible to be jealous of a two-month-old?! Look at that stylish cot!

Ellen says she is smitten with her growing family. "I try my absolute hardest every minute of the day to be the best mother I can to those children," she said in an interview.

"Not having a mother growing up, being a mother is more significant than I can put into words," she added.