As Life & Style revealed earlier this week, Kourtney Kardashian is pregnant with her fourth child — though the baby daddy's identity still remains a mystery!

While most fans assume the father is Scott Disick, the 37-year-old mom recently spent time with boytoy Justin Bieber, who a source reveals is eager to become a parent.

RELATED: Blac Chyna and Rob Kardashian Are Having Twins!

“Justin would love to have a child with her," an insider says of the 22-year-old pop star. "They even used to joke about co-parenting a mini Bieber.”

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Kourtney and Justin in October 2015.

But not everyone was happy over the former flings' reunion. “Scott was pissed and kept questioning why she ran to see him," the insider explains. "Kourtney had been telling everyone Justin was ‘just a hookup’ and ‘too young to take seriously.’"

For now, a lot of details remain up in the air. “A paternity test is the only answer at this point, but it’s the last thing in the world [Kourtney] wants to do,” the source concludes.

For more on Kourtney’s pregnancy, pick up the latest issue of Life & Style, on newsstands now!

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