The former Wonder Years star and bestselling author gave birth to her first child Tuesday night, a boy named Draco Verta. He weighed in at 7 lbs., 2 oz. and takes his moniker – which means dragon – from the constellation of the same name.
"We are humbled, overjoyed and so grateful for this miraculous gift," McKellar and husband Mike Verta tell PEOPLE in a statement. "It's like we've only now just learned the true meaning of love."
McKellar, 35 – now a mathematician and author of three books on the subject, including current bestseller HOT X: Algebra Exposed – wed composer Verta in March 2009. They announced the pregnancy one year later.
Reporting by KATE COYNE