The Big Reunion star and his wife, who prefers to remain private, are expecting their new arrival "anytime soon".
Sean, who will be a first-time dad, catapulted back to fame last year when he reunited with his bandmates for the ITV2 reality show.
Sean is now the second band member of 5ive to be expecting a new arrival, as father-of-two Scott Robinson will soon be welcoming twins with his wife Kerry.
Sean's bandmate Ritchie Neville first broke the news on Twitter this morning, saying that there are now three babies on the way. He told fans: "Three @official5ive baby's due imminently, very excited to have some more additions to the crew @SeanConlonMusic @Scottlarock5."
A rep for Sean later told Reveal: "Scott and Kerry are due twins imminently and Sean and his wife are also expecting the arrival of their baby anytime soon."
The couple have yet to release any details on the sex of their unborn baby, but with three new additions on the way, there could be a mini 5ive group forming right before us!
See more stars who have announced pregnancies this year:
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