AJ McLean will soon be dad to two daughters!

The Backstreet Boys star revealed on Instagram that his wife, Rochelle Karidis, is expecting a baby girl. The duo is already parents to four-year-old Ava Jaymes.

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"Out of the millions of pics I've either been in or taken of my two loves my wife and my daughter nothing will ever ever ever amount to this one pic," he wrote next to a photo of Ava kissing her mom's belly. "This is what life is about and this is love at its best."

He continued, "Ava baby your [sic] gonna be the best big sister in the world and I cannot wait to see you and your Lil sister side by side. I'm so proud as a father to be able to be present and so in tune with my family."

The couple announced the pregnancy on Labor Day with a photo showing four pairs of Air Jordan sneakers. "So the McLean family will be expecting a new addition to the family next spring!!!" the 38-year-old wrote at the time.

Congrats to the soon-to-be family-of-four! Scroll through the gallery below to see more of the best pregnancy announcements of 2016.