Inside Kim and Kourtney Kardashian's Night Out With Scott Disick and Sofia Richie

It marked another rare joint outing for the former couple and his girlfriend.

Art brings everyone together.

Kourtney Kardashian, along with sister Kim Kardashian and friends, joined her ex Scott Disick and Sofia Richie on a night out in West Hollywood on Friday, marking another rare joint outing for the former couple and his girlfriend.

The group attended the opening of the ArtLife Gallery's Street Dreams exhibition. Kourtney, Scott, Kim and Larsa Pippen and Brittny Gastineau were photographed together inside. Scott and Sofia, who wore a brown cowl-beck mini dress, were photographed arriving at the exhibit.

"Scott and Sofia arrived at the gallery first and were touring the exhibit when Kourtney arrived," a source told E! News exclusively, adding that the women were later seen chatting.

"Kim arrived on her own, to the surprise of her sister, who didn't seem to know she was planning on attending," the source added.

The entire group ended up going out to dinner afterwards, the insider told E! News.

Later that night, Scott and Sofia were spotted leaving the nearby celeb-favorite restaurant Craig's. Kourtney and Pippen were later photographed exiting the eatery as well.

Another source confirmed Kim and Brittny were also with the group and said Kourtney, Larsa and another friend dined with Scott and Sofia at the same table.

Kourtney wore a cream sleeveless plunging top and high-waisted black pants on the group's night out.

Kim sported a gray sleeveless top, skintight silver pants.

Kourtney and Sofia, who began dating Scott last year, were not photographed together. They have never been. 

The group's outing comes less than two weeks after Scott, Sofia and Kourtney had dinner together at another restaurant, marking the first time they were all seen together in public.

"Scott and Sofia are very serious and Scott felt it was important that Sofia and Kourtney interact and bond," a source told E! News at the time. "They have kept things separate for over a year now, and Kourtney is now more open and willing to have a surface level relationship with Sofia."

The source also said, "Scott and Kourtney both agreed it is better to get the elephant out of the room and for them to all be in each other's lives in order to make things flow easiest for the sake of the kids."

Sofia has occasionally spent time with Scott and Kourtney's three children, Mason, Penelope and Reign.

The former couple has been committed to co-parenting their kids since their 2015 breakup and have even occasionally taken family trips together. Earlier this week, fans were thrilled by a photo Kourtney posted on Instagram that shows her, Scott and their sons during their October visit to Bali.

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