When it comes to baby names, Kourtney Kardashian is a pro. The mother-of-three admits that each of her children's names has a lot of thought behind them — especially her four-month-old baby, Reign.

The reality star added that she waits until each child is born before she officially decides on a name, but once she landed on Reign Aston, she was sold.

“I actually had the name on our list with Mason,” she told 'People.' “Then with Penelope, I had it on the list but spelled R-A-I-N.”

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But the name didn't suit her other two children, which is why she held out for her third.

“Once I found out I was having a boy, we just changed the spelling again,” she said.

reign disick
Instagram

Reign Aston.

The 35-year-old waited months before giving the world a glimpse of her adorable little boy — but two weeks ago, she finally caved and shared Reign's first photo on Instagram.

"My little turtle dove angel baby boy Reign Aston Disick," she wrote.