The singer and her director husband Barnaby Clay welcomed a baby boy, and Karen took to on Sunday (27Sep15) to share the happy news.

Posting a black-and-white photo of herself cradling the little one in her arms, she added the caption, "Shortly after we brought him home I held him in my arms and listened to Roberta Flack singing this tune I felt my heart exploding in my chest with a love I couldn't begin to put into words so Roberta's will have to do for now.

"The first time ever I saw your face / I thought the sun rose in your eyes / And the moon and the stars were the gifts you gave / To the dark and the endless skies, my love / To the dark and the endless skies."

Karen O has been married to Clay since 2011.