TheKeeping Up with the Kardashians star, who's currently filming her new spinoff Kourtney & Khloe Take the Hamptons, kicked Disick out of the family's rented $14 million estate in the Hamptons on June 9 after a big argument, Us Weeklyreported.
"Kourtney was yelling at Scott after she found an inappropriate picture of him with another girl," a Kardashian source told Us of the couple, who have a third child on the way and are already parents to son Mason, 4, and daughter Penelope, 23 months.
Disick, 31, has reportedly resorted back to his old wild partying ways this summer and Kardashian, 35, is fed up and constantly fighting with her man.
Kardashian confronted Disick in the driveway and, according to the Kardashian source, she exclaimed, "You need to be a more responsible father and get better. There is another baby on the way! You need to straighten up or get out!"
An insider told the magazine that when Disick got the boot from the Kardashians' house, he stayed the night at the nearby Southampton Inn and "looked stressed." Ironically, both of Disick's parents have died unexpectedly within the last eight months.
Kardashian is "worried" about Disick's behavior and "hopes the new baby will be a wake-up call," added the Kardashian source.