Jessica Capshaw introduced her new baby daughter to the world, and she couldn't be cuter!

"I am endlessly grateful for her safe arrival and my heart is so full of love that it threatens to burst," Capshaw wrote next to the heartwarming photo of the adorable new addition to her family.

WATCH: Stars Share Pics of Their Cute Kids

The 39-year-old Grey's Anatomy star and her husband, Christopher Gavigan, welcomed their fourth child, Josephine Kate Gavigan, last Monday.

Capshaw and Gavigan, who tied the knot in May 2004, have an 8-year-old son, Luke Hudson, and two daughters -- Eve Augusta, 5, and Poppy James, 3.

WATCH: Celebrity Babies Due in 2016

Capshaw shared the news that she was expecting back in December with a super sweet family photo which she posted to Instagram.

"This year our family has reason to further broaden our smile," she captioned the smiling snapshot. "Baby number four is on the way!! I am a lucky, lucky girl."

WATCH: They're Having a Baby! Hollywood's Best Celeb Pregnancy Announcements

Congrats to the happy family!

For a look at some other celebs who are getting ready to welcome their own bundles of joy this year, check out the video below.