The former NFL star and his wife are already parents to daughters Wyatt, Elliotte, and Bennett
"I got it pretty easy, I'm not gonna lie," he told the outlet. "There's another girl, so the clothes are all going to be hand-me-downs or already bought. The crib is already situated. So we're pretty set. Kylie's definitely preparing more than I am, because she's actually growing the human being."
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Related: Kylie Kelce Reveals She and Jason Are Expecting Baby Girl No. 4 in Hilarious Photo of Their Three Daughters' Reactions
He continued to rave over his girls as he shared his excitement for their newest addition.
"I love my kids so much, and especially my daughters," the soon-to-be dad of four shared. "I was telling somebody out there because they're expecting their first -- and they look at you. They smile at you. There's just a way that kids have to warm your soul in a way that nothing else can."
"And it's been such a blessing to have three healthy, smart, wonderful children. And hopefully we'll welcome a fourth into this world, and we'll be able to watch them fight and tear each other apart and all the good stuff."
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While Jason absolutely loves raising his little ones, he revealed the part of parenting that he finds most challenging, saying, "I think the most challenging thing as a parent is patience, by far."
He continued, "The most rewarding thing is just smiles. To me, seeing them smile or seeing them laugh -- like nothing in this world makes you feel better."
Possibly even more excited than Jason and Kylie are his parents Ed and Donna Kelce, who Jason jokes constantly get to play good cops.
"Everybody's excited, anytime you find out," Jason shared. "And you know, Mom and Dad, they got the best stage in being grandparents. They get to go and spoil them, really have fun with them, and then hand them back, so we're the ones that got to be the bad cops. So they're excited, for sure."