Khloe Kardashian is a first-time mom.
TMZ reported Kardashian gave birth around 4 a.m. ET at a hospital outside Cleveland, Ohio.
Sources said her mom, Kris Jenner, and sisters Kourtney and Kim Kardashian were by her side in the delivery room.
The news follows reports Kardashian's boyfriend, Tristan Thompson, was unfaithful during her pregnancy.
Insiders said the 27-year-old Cleveland Cavaliers player was present for his daughter's birth.
Thompson shares her 16-month-old son, Prince, with ex-girlfriend Jordan Craig.