Heidi Montag and Spencer Pratt just became an aunt and an uncle!

The Hills star’s older sister Holly Montag, who briefly appeared on the reality series, gave birth to a baby boy named Isaiah Hawk on May 3, a source confirms to ‘Us Weekly.’ He weighed in at 7 lbs., 5 oz.

heidi montag

Holly and Heidi in 2008.

This is the first child for the 31-year-old and her husband, Richie Wilson, whom she married in September of last year.

Heidi previously revealed that her sibling���s pregnancy had actually convinced her to hold off on having kids.

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“I was like, ‘I think I can put this off for a little bit because you look REALLY uncomfortable,’” she told ‘Us.’ “I’m three years younger. Maybe I can wait three more years to catch up.”

Congrats to the new parents!