Scott Disick has thanked his ex Kourtney Kardashian for being "the best baby maker in town".

Scott Disick and Kourtney Kardashian (c) Instagram

Scott Disick and Kourtney Kardashian (c) Instagram

The 37-year-old star paid a gushing tribute to his former partner, who he shares three children with, on Instagram as the former couple celebrated the birthdays of their sons Mason and Reign on Monday (14.12.20).

Alongside a snap of their youngest children, daughter Penelope, eight, and Reign, six, Scott wrote: "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, I love u and our family more (than) anything in the world (sic)."

It was recently reported that Kourtney "likes" it when Scott – who she was in a relationship with between 2006 and 2015 - is happy romantically as it makes him a "more responsible" parent.

A source said: "Kourtney likes when Scott is dating someone, because that's when he's the most grounded, happy and responsible as a parent. That's how the family saw him when he was dating Sofia [Richie], and it's the same way now that Amelia's in his life."

The 'Keeping Up with the Kardashians' star – who has also shares 11-year-old son Mason with the 'Flip It Like Disick' star - is believed to be supportive of Scott's rumoured new romance with Amelia Hamlin, just as she was when he was together with former beau Sofia Richie.

The insider added: "He continues to be there for their three kids just like he was when he was dating Sofia Richie."