The couple named the baby boy Isaiah Hawk Wilson. Isaiah weighed in at 7 pounds, 5 ounces.
Montag and Wilson have been married since September 2014 and announced the pregnancy in January.
But what about Holly's little sister, Heidi? The younger Montag told Us Weekly that witnessing her sister's pregnancy has made her "actually kind of the opposite [of wanting kids]."
Sorry Isaiah, no cousins anytime soon!
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