Scroll down to read the rest of their confessions.
"If there was a stoner [in your family] who would it be?" asked Oliver. "No one knows that so that's the first time I've ever really said anything out there", she said. Not much else was said about the topic of marijuana.
The audience will get the answer in the next episode of the long-running family show, which is set to return on September 17.
The pair also revealed that Kylie is the most laidback and "non-judgemental" of the family, before discussing how their show KUWTK (which is now coming to an end, agh!) came about. This revelation comes a few years after Kim Kardashian admitted that she was high on ecstasy during a pivotal life moment.
After they filmed in the stores, the production crew started filming scenes with the family at dinner, with Kourtney adding, "I think they just made a decision to do a family show".
Kourtney then said, musing if this could be the possible reason she's always a target: "Everybody's always saying something about me". "I did ecstasy once and I got married".
When asked if they look back at older episodes, Jenner said she will only watch if it's a "really old" episode. "Like, everything bad would happen".
"Absolutely. Everyone knows it", Kardashian West said. "Like, my jaw was shaking the whole time", she confirmed. I'm not like that anymore.
Kim Kardashian has teased fans with her unexpected question about Scott Disick and his ex Kourtney who have been spending a lot of time together after split from young model Sofia Richie.