Meredith's a proud mom! Ellen Pompeo gushed about her daughters Stella, 5, and Sienna, 6 months, during an appearance on The Ellen DeGeneres Show on Wednesday, Mar. 4. Not only has her eldest been a fantastic big sister, but she also wants to follow in her famous mom's footsteps — well, sort of.

The Grey's Anatomy actress, 45, explained that Stella often visits the set of her show, and now wants to become an emergency room doctor.

"It's hilarious. Adorable," Pompeo said. "Every time she comes to set the first thing she wants to do is — Linda Klein is our medical producer, wonderful woman, good friend of mine — she just wants to go straight to Linda’s office and play with all the medical things. All the fake organs."

"Yesterday I went in to find her, I couldn’t find her, she was in Linda's office with Linda with a bone drill, drilling a fake femur bone with a real bone drill," she adding, laughing. "I mean she was supervised, but you know they have her doing advanced procedures."

Stella may have jumped right into a Meredith Grey-like role, but she was much more hesitant when she first met Sienna. Pompeo and her music producer husband Chris Ivery announced back in October that they had secretly welcomed the little tot via surrogate.

"She liked her at first. And then she said, 'Is she leaving?' I was like 'No, no, she's gonna live here,'" Pompeo said. "She had about a month where she was not in a good mood. Bad mood every day for a month. And now that passed and now she’s fine." She added: "[Stella] loves her!"

As for whether Stella holds her sibling? "We try, but Sienna's kind of big and Stella’s pretty petite," Pompeo explained. "So we have to sort of supervise the holding."

Watch the cute video above!