Anthony Williams

Anthony Williams was the adopted son of Amy and Rory Williams. Born around 1946, he was brought to his new parents' home (WC: Rory's Story) in New York City. (PROSE: Summer Falls: Introduction) He was also the brother of River Song, who was born to Amy and Rory as Melody Pond, (TV: A Good Man Goes to War) and the brother-in-law of the Doctor, (WC: Rory's Story) River's husband. (TV: The Wedding of River Song)

In 1946, a week before Anthony came home, Rory recorded a special message for his child using a smart phone from the future. He told his son how relieved he was was World War II was over and how impressed he was at people for their resilience through those difficult times. Previously, Rory had recorded chapters telling Anthony how he first met Amy at Leadworth Primary School, how they got engaged and of the many dangerous and deadly adventures he had with the Eleventh Doctor. As he prepared to dictate a chapter he called "I'm the pretty one", Amy called Rory over to stop messing around and help paint Anthony's bedroom. (WC: Rory's Story)

Behind the scenes
Anthony Williams first appeared in P.S. an unfinished story written by Chris Chibnall that explained how Brian Williams learned the fate of his son Rory and daughter-in-law Amy. Originally meant as a filmed DVD extra, the scene was cancelled due to actor unavailability and shared in 2012 as an animated short online.

Though his initial appearance was "unfinished" and therefore an invalid source, Anthony Williams was later mentioned as living in New York City with his parents Amy and Rory in the About the Author section for his mother in the anthology Summer Falls and Other Stories. He was again mentioned in the webcast Rory's Story written by Neil Gaiman, in which Rory records an autobiographical message for his infant son, who would soon be brought home.

In P.S. Anthony's full name was Anthony Brian Williams. He was adopted by Amy and Rory, a fact implied but not explicitly stated in Rory's Story. Raised in New York City, he was made aware that his parents travelled through time, and was charged with delivering a letter to his paternal grandfather Brian Williams a week after his parents' final departure from Great Britain and their home era, explaining why they never returned after the Year of the Slow Invasion. He brought with him family photo albums and other mementos to show Brian. When all was revealed, Brian welcomed Anthony with a warm embrace. (NOTVALID: P.S.)

While also unstated, Anthony's adoption lines up with the revelation in Asylum of the Daleks that Amy was no longer able to bear children of her own after the events of A Good Man Goes to War.