The sister of Heidi Montag welcomed her first child, son Isaiah Hawk Wilson, on Sunday, 3 May. He weighed 7lbs 5oz.
A rep for Holly told People that "the whole family is doing well" and said the couple felt "blessed" about their new arrival.
Holly announced her pregnancy over Christmas, just a few months after she married boyfriend Richie Wilson in a fairytale ceremony in her Crested Butte, Colorado hometown.
The location is familiar to fans of The Hills as we often saw Heidi and Holly returning from LA to visit their parents.
Congrats to Holly and Richie!
Meanwhile, sister Heidi has spoken out often about her desire to have a child, most recently in January when she and husband Spencer Pratt appeared on the US reality show Marriage Boot Camp.
Heidi explained: "We've been married for six years. We are in boot camp to get over our regrets about the past and fear about the future. I'm ready to have children and Spencer is acting like a child and not ready for one."
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