Time is flying for former Bachelorette Desiree Hartsock!

The 30-year-old is expecting her first child with husband Chris Siegfried, and is showing off her huge baby bump on Instagram.

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"Well, that went fast. #35weeks and counting," she captioned a cute mirror selfie.

Just weeks before her due date, the couple — who tied the knot in 2015 — also revealed that they're having a baby boy.

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"We are so excited to share that we will be having a little baby BOY," she wrote. "Our hearts are so full of love for our little man already and we can't thank you all enough for the extra love you've shared during this special time!"

We can't wait to meet him! For more Bachelor Nation baby updates, check out the gallery below.