The Bieber brood is getting bigger! Justin Bieber is about to be a big brother again—this time, to a new baby sister, sources confirm to TMZ.

Justin's father Jeremy's new bride, Chelsea Rebelo, is reportedly pregnant and expecting a daughter. Chelsea is "about 16-20 weeks along," per TMZ.

Earlier this week, Jeremy and Chelsea were married during a pink-themed wedding—perhaps in honor of their new daughter?—in Montego Bay, Jamaica on Monday, February 19. Justin and his on-again, off-again girlfriend Selena Gomez were in attendance.

Chelsea and Jeremy became engaged in St. Barts earlier this month.

The baby girl will be Justin's third sibling behind half-brother Jaxon (born 2010) and half-sister Jazmyn (born 2009), both Jeremy's children.

Justin, who was born March 1, 1994, is the only child of Jeremy and mom Patricia Mallette. His parents were never married.

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