Sean and Catherine each announced the news on Instagram, and told Life & Style Weekly that they are "so thrilled to announce that we're expecting! Thank you for all the love and support you've given us over the years. We can only hope to be half as good of parents are [sic] our parents were to us."
"It's happening! I'm going to be a dad," Lowe captioned his photo.
Sean and Catherine got engaged on Season 17 of The Bachelor and tied the knot in January of 2014.
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