Jeffrey Dean Morgan, Hilarie Burton Welcome Baby

 Jason Merritt/Getty Images

Grey's Anatomy alum Jeffrey Dean Morgan, 44, and his girlfriend, former One Tree Hill star Hilarie Burton, 27, quietly welcomed a baby boy a few months ago, reports the new Us Weekly (on newsstands now).

The source tells Us Weekly the two began dating in 2009, and "their relationship moved really quickly."

The actress, who divorced One Tree Hill assistant director Ian Prange in 2008, was not photographed in public between May 6, 2009, and April 20, 2010. For his part, Morgan is already familiar with daddy duties: He learned just last March that he had a son, now 5, with actress Sherrie Ross.

"She would be a fantastic mother," Burton's ex Prange told Us recently.

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