Scott Disick and Kourtney Kardashian share three children: Reign, 6, Penelope, 8, and Mason, 11

By Jen Juneau
December 15, 2020 08:34 AM

Scott Disick couldn't be more thankful for the mother of his children, Kourtney Kardashian.

In a heartfelt Instagram post on Monday (which also marked the sixth and 11th birthdays of their sons Reign and Mason, respectively), Disick, 37, expressed his appreciation for his ex alongside a photo of the pair with Reign and daughter Penelope, 8, posing on a staircase.

"Thank you @kourtneykardash for being the best baby maker in town, I couldn't have asked for a better person in the world to have these amazing children with," Disick addressed Kardashian, 41.

"I love u and our family more than anything in the world 🌎," he added.

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Credit: Scott Disick Instagram
Scott Disick and Kourtney Kardashian
| Credit: David Becker/WireImage

Disick and Kardashian ended their nine-year relationship in 2015, but have remained amicable co-parents — and even joked about having a fourth child together recently, in the Keeping Up with the Kardashians season 19 finale.

The exes have since dated other people (perhaps most notably for Disick, Sofia Richie, whom he split from in August). And while a source recently told PEOPLE that the Flip It Like Disick star is not in a rush to start dating again, he has been spotted several times with Amelia Hamlin since late October.

On Thanksgiving, Hamlin, 19, shared a series of photos on her Instagram Story of the people she's lucky to have in her life – her family, friends and Disick. "Thankful 4 these ppl," she captioned a photo with Disick and another friend on her Instagram Story.

Caitlyn Jenner noted in September that she was hopeful Kardashian and Disick would get back together eventually, saying in part, "They've got all these kids together. I think always it's the best for the kids to have a mother and a father that's right there all the time."

Scott Disick and Kourtney Kardashian with their kids
| Credit: Kourtney Kardashian/Instagram

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Over the weekend, Disick celebrated Mason and Reign's birthdays with a gathering at his home. The father of three shared photos on his Instagram Story, including an image of Reign holding a white snake in his arms.

"Happy birthday," Disick wrote, going on to share a snapshot of silver balloons that spelled out Mason and Reign's names.

The Poosh founder also posted multiple images of the boys to her Instagram Story on Monday to celebrate their joint birthday, writing, "I'm crying" and "Thankful" atop two snapshots of the brothers.

"Happy birthday to these two beautiful boys of mine who I love so much!!" proud grandmother Kris Jenner shared on Instagram, alongside a series of photos of the boys. "Mason and Reign you are both such a big part of my heart and I'm so very proud of you!!! You bring such joy and happiness to our entire family and we love watching you grow ... you are the most amazing grandsons and I love you more than you will ever know ... Lovey ❤️🙏🎄🥰😍 #family #memories #love."