'Bachelor' Sean Lowe and Wife Catherine Are Expecting Their First Child!

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The Bachelor family is about to get even bigger.

Former suitor Sean Lowe and wife Catherine -- who got engaged during the 17th season of the dating competition and tied the knot a year later -- are expecting their first child. Lowe shared the good news on Instagram, writing, “It's happening! I'm going to be a dad!”

"Sean and Catherine are very excited. She's about three months along -- due early summer,” a source close to the couple told ET. “They kept it really quiet -- they only told their family. They want to take this time to be themselves now, because they knew once the news got out, its everyone’s baby! They won’t find out the sex of the baby. If they change their minds and do find out, they wont release it.”

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So, what’s the key to finding love on TV? “The only thing I ever tell people is to look past the fancy dates and really look at the woman," Sean told ET. "Look at her heart and see if you can imagine spending the rest of your life with her."

As for the next suitor, Ben Higgins, the couples hopes he “can join the married club.” "I think he's sincere in the fact that he really wants to find a wife," Sean told us. "I think he's a great guy looking for a good girl with good morals. So I hope one of the 25 is a good match so he can join the married club with us."

Ben's Bachelor journey kicks off Jan. 4 on ABC, while Sean and Catherine will soon star on Marriage Boot Camp. Find out the real reason they signed up: