We gotta hand it to Kourtney Kardashian for handling her split from Scott Disick like a champ. While he's been busy partying with all sorts of trashy girls at his new Beverly Hills bachelor pad, Kourt has stepped out with a smile on her face and taken care of the former couple's three children.

On Friday the 36-year-old reality star left a lunch at the Montage in Beverly Hills, and we're not sure how she managed to look so chipper on her way out the door, but she couldn't stop smiling when X17 photographers snapped her picture. The same day a bunch of scantily-clad girls were seen arriving at Scott's new crib for what seemed like a pool party. Gross!

"He's gotten away with so much for so long, he believes he's immune to anything they can throw at him," a source told Star about Scott's behavior. "But the truth is, it's not going to take much for the Kardashians to ruin him completely." The insider added, "They aren't messing around. If it weren't for the Kardashians, Scott would be a broke, drunk nobody. Everyone in the family feels completely betrayed by Scott. Kris truly looked at him like a son. Kourtney has a producer credit and Scott doesn't, so it's easy to get rid of him. Unless he goes to rehab, E! will drop him completely." Damn!

Kourt took the kids to the zoo on Thursday, and when she was at her meeting on Friday Khloe was in charge of Penelope ... and Kim's daughter North! Khloe Instagrammed a few photos of the girls watching movies, and it looks like the group had a blast: