Now, out of the Jenner and Bieber (née Baldwin) friendships, Kendall and Hailey’s BFF status might be more well-known. However, as Kendall revealed in past interviews, it was actually Kylie who introduced the pair as she was friends with Bieber first and brought the three together.In the season 3 kick-off of the latest Who’s In My Bathroom, the episode reminded viewers that the original duo still remain very good friends. In a festively themed Halloween special, Kylie Jenner and Hailey Bieber were decked out in green face paint and dressed as spooky witches, proving their long-standing friendship still exists and that it's stronger than ever.

Kendall And Hailey Were BFFs From Modeling

Fact: the Jenner sisters and Hailey go way back, but Kendall spilled how the friendship actually started. “[Hailey] was actually best friends with Kylie, and I was good friends with her cousin Ireland [Alec Baldwin‘s daughter],” revealed Jenner.

Related: Kendall Jenner Laments "Out Of Hand" Narrative About Her Family

The trio grew close when the sisters would visit New York where Bieber lived at the time, and once Kendall started modeling, Kendall and Hailey grew closer since they were working in the same industry. “From then on, she was my homie,” said Jenner.

But as the saying goes: three’s a crowd. Initially, the burgeoning friendship caused friction. Jenner shared, “At first, Kylie was mad; I had to bring them back together and be like, ‘No, it’s okay, guys.’ But it’s all good; that’s our love story.”

Kylie And Hailey Grew To Be Friendly Over Time

It’s no secret that Hailey’s husband is none other than pop superstar Justin Bieber. After getting back together and embarking on a whirlwind romance in 2018, the pair surprised everyone and got married within two months of dating in a New York City courthouse.

The Biebers followed up with an intimate wedding ceremony in South Carolina the next year attended by some of their closest and most famous friends. And this, of course, included the Jenner sisters, namely Kylie, who came with her baby Stormi as her plus one.

In 2017, it was a shock to pop culture when Kylie, then 19 years old, announced she was expecting with rapper Travis Scott. There was plenty of backlash regarding her pregnancy, which included naysayers making negative comments about her age.

Related: 10 Sweet Facts About Kylie Jenner's Relationship With Stormi

But Bieber, unlike the haters, congratulated her long-time friend, commenting that she is super excited for her and that Jenner has shown maturity and “...she’s going to be the best mom ever.

The Three Best Friends That Anyone Could Have

Fortunately, despite the initial drama, it’s become clear that the Jenners and Bieber keep in touch and remain close. Sounds odd, but they even celebrate their exes’ success together.

To the surprise of concertgoers, the trio was spotted at a Harry Styles concert in Los Angeles, who Kendall had briefly dated in the past, dancing, singing, and having an all-around good time.

If the Harry Styles concert outing wasn't proof enough, Kylie and Hailey, along with Justin, who counts Kendall as a good friend of the couple, have all attended and supported Kendall’s 818 tequila promotional parties.

For those not in the know, 818 is a tequila company that Jenner launched in 2021. So, guess who made the guest list when she threw “an invite-only” bash at Coachella? Yep, Kylie and the Biebers were there to toast the model’s continued success in the spirits world.

Fast Forward To Today, Kylie And Hailey Still Support One Another

In the Halloween episode of Who’s In My Bathroom, Hailey and Kylie get into plenty of shenanigans, courtesy of their BFF, Kendall, and her 818 tequila. But as they sip cocktails and throw back tequila shots, the two also endearingly took time to celebrate each other’s successes.

Bieber commended the growth of Jenner’s cosmetic empire, Kylie Cosmetics, "I've always been so inspired by that.” And Jenner threw the compliment right back. “First, I want to say that I’m so proud of you and that I love Rhode,” giving a shout-out to Bieber for starting her own skincare line.

“I remember when I used to compliment your skin when we were like 16,” she said. “You used to tell me about these products and ingredients, and I didn’t even know what that meant at that time.”

Related: Kendall, Kylie And Hailey Bieber Cook A Holiday Meal: Here's What They Ate

Jenner continued, “[Kylie Cosmetics] been through a lot. I’ve grown so much, and I’ve learned so much about makeup, and it really is my passion.”

“That really shines through, and I think you really see that through your products,” echoed Bieber.

To end the special, the two indulged in a bit of cheeky fun and friendly competition, playing games like cauldron pong, followed by a round of shots, or two, and concluded the day with the infamous photo that circulated social media of witchy Kylie lounging in Hailey’s bathtub. (Pst, see if you can spot Mr. Bieber in a spooky cameo.)