The actress, who plays popular doctor Meredith Grey in the hit series, gave birth to baby Stella on September 15.
And she's clearly thrilled to be a new mum. The 40-year-old could barely stop smiling as she showed off a photo of her daughter in the arms of her husband, music producer Chris Ivery, 42.
And dad, it seems, is just as smitten – the picture showed little Stella wearing a red-checked shirt matching his.
"Chris – he loves dressing her up like him," she said.
"He goes out and buys her clothes that look like his clothes."
But baby Stella is going to have something different to wear from now on.
At the end of their talk, presenter Ellen handed her guest an "I Heart Ellen" babysuit for the tot.
The star's appearance also included a thank-you to her nanny, who helps look after Stella when she was in front of the cameras.
"I couldn't do it without her," she said.
Grey's Anatomy airs at 10pm on Thursdays on Living.