Billy Joel turned a Fourth of July party into a surprise wedding Saturday, marrying pregnant girlfriend Alexis Roderick at his sprawling Long Island estate.

The ceremony was presided over by Gov. Cuomo, a longtime friend of the singer-songwriter, People magazine reported.

Joel, 66, and Roderick, 33, are expecting their first child, a girl, later this summer. They have been together since 2009.

“Billy is thrilled to become a dad again,” a source told People.

Joel’s daughter, Alexa Ray, 29, was at the intimate gathering.

Her mother, Christie Brinkley, posted a photo of the newly married couple on Instagram above the caption, “Congratulations to the glowing bride and groom.”

It’s Joel’s fourth marriage.

This article originally appeared in the New York Post's Page Six.