Anthony Williams

Anthony Brian Williams was the adoptive son of Rory and Amy Williams, adoptive brother of River Song, and adoptive grandson of Brian Williams. Because River married the Eleventh Doctor, Anthony is his brother-in-law.

Biography
Anthony Brian Williams was adopted by Rory and Amy Williams in 1946. He outlived his parents, and was made aware of their having traveled through time, being charged with delivering a letter to grandfather Brian Williams explaining why they never returned after The Year of the Slow Invasion. When all was revealed, Brian welcomed Anthony with a warm embrace. (WC: P.S.)

Behind the scenes

 * According to an unshot scene scripted by Chris Chibnall, Brian received a note from a man named Anthony while he was watering Amy and Rory's plants a week after they last left. It was from Rory and read that he and Amy were trapped in New York fifty years before Rory's birth. It also said that he missed Brian and Anthony was Rory's son, whom he adopted in 1946. He asked Brian to take care of him.