Kanye and Kim Kardashian West are expecting their fourth child via surrogate, PEOPLE confirmed Wednesday morning

Six might be the perfect number for Kanye West and Kim Kardashian West‘s immediate family.

Following word that the couple are expecting their fourth child together, via surrogate, a source tells PEOPLE, “They’ve got to be over the moon” about the “wonderful news” of their little one on the way.

“They’ve always talked about wanting four kids: two boys and two girls,” the insider explains of West, 41, and Kardashian West, 38. “That’s always been the plan.”

“They definitely want a boy,” the source adds of the rapper and reality star, who are already parents to daughters Chicago, 1 this month, and North, 5½, plus son Saint, 3.

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Credit: Kim Kardashian West/Instagram
Kanye and Kim Kardashian West
| Credit: Taylor Hill/FilmMagic
The West family
| Credit: Kim Kardashian Instagram

PEOPLE confirmed the baby on the way via surrogate on Wednesday morning.

And although Kardashian West has made it clear that she loves being a mother, in August, a Keeping Up with the Kardashians source told PEOPLE that she and West weren’t “in a huge rush” to give their three children another sibling.

“They have absolutely talked about trying for another baby with the help of a surrogate, but nothing seems decided for sure,” said the insider, adding of the couple’s then-7-month-old daughter, who is the only one of their current children to be born via gestational surrogate, “Chicago is still little, and they have time.”

“They don’t seem to be in a huge rush,” the source further revealed. “They would use the same surrogate if she agrees to help them again. Kim can’t say enough kind words about the surrogate.”

The West family
| Credit: Kim Kardashian West/Instagram

RELATED VIDEO: Kim Kardashian West Warmed to Surrogacy Because “She Really Misses Having a Baby in the Family”: Source

Though Kardashian West has been candid about her fears surrounding surrogacy and how she thinks it “is so much harder” than pregnancy, she opened up in May about how it ultimately was an overwhelmingly positive experience.

“I would have maybe one more [child],” she admitted. “I really, really enjoyed the surrogacy process. I will say, when it came to the breastfeeding time, I was like, ‘Okay, this is the best decision I ever made.’ ”

The KKW Beauty mogul also said in an April cover interview with Ellethat although “my home and my heart feel really full right now,” she wasn’t ruling out another baby — but she was drawing the line at four kids.

“I don’t think I could handle more than that. My time is spread really thin,” Kardashian West admitted. “And I think it’s important that in all couples, the mom gives the husband as much attention as the kids.”