AceShowbiz -

Scott Disick was on his fatherly duty when he took two of his three kids, Mason and Penelope, to Las Vegas for a paid promotional event for the opening of the Sugar Factory Las Vegas restaurant and candy store on Saturday, March 18. However, Scott's ex-girlfriend Kourtney Kardashian was reportedly not pleased as she was worrying a lot if he could handle the kids.

"Mason and Penelope went with Scott to Las Vegas this weekend and were chaperoned the entire time by Kourtney's team of security," an insider told RadarOnline.com. "Scott cannot do anything with those kids without her knowing exactly where they are, what they are doing and who they are with."

Citing the source, the news outlet claimed that Kourtney asked the 33-year-old restaurateur to keep his phone accessible and on at all times. "Kourtney does not really care about what happens to him because he makes her sick. She only cares about her kids," the source added.

An eyewitness told E! News that Scott posed alone for photos outside the eatery while the security accompanied the kids across the red carpet. According Celebrity Insider, he brought along a personal photographer at the event to take pictures of him spending some quality time with the kids.