Kelis' baby decided it was time to make like a fetus, and head out. 

Kelis named her new baby boy, Knight Jones.

Knight Jones -- who weighed 7.8 lbs. -- was born Tuesday around 9 p.m. in New York City. Adds the rep, "The beautiful baby boy and his mother are doing wonderful." Kelis had been in labor since 2 a.m. Monday and had a natural birth, with her mother and sister by her side in the room.

The baby daddy is rapper Nas, who is currently in a nasty divorce battle with Kelis. She's a tough bitch and will handle raising a baby on her own just fine. Congrats on the new baby boy, Kelis!