After 66 years of not knowing his origins, David Stevenson has connected with his birth relatives. Stevenson was discovered as a newborn in a locked apartment corridor in London in 1960. His journey to uncover his past was documented in an episode of ITV's "Long Lost Family Born Without Trace."

During the program, Stevenson learned that his mother, Petra, was from the Netherlands and grew up in a strict Catholic household. Her relatives explained that a pregnancy outside of wedlock would have been unacceptable, and they never knew she was pregnant.

Initially, residents of the apartment building where Stevenson was found were investigated, but no leads about his parents emerged. He was subsequently adopted by the Stevenson family and had a happy childhood.

Stevenson, now with a family of his own, initiated a national appeal for information in 2009 with his wife Julie. This effort marked the beginning of a decade of investigative work that eventually led to DNA databases, revealing his Dutch and French heritage.

The "Long Lost Family" team, led by social worker Ariel Bruce, identified a Dutch family with whom Stevenson had a strong connection. DNA tests on two family members confirmed his mother was Petra, who passed away in 2010. Relatives noted a resemblance between Stevenson and Petra when shown a photograph of her.

Stevenson expressed sadness upon learning about his mother's difficult circumstances. "You know, having given up the one child that she did have," he said.

He then received a letter from his relatives in Rotterdam expressing their desire to meet and share information about Petra. This led to an emotional reunion in the Netherlands with his aunt Marianne, his cousins Saskia and Bart, and another cousin, Jan.

"One of the most rewarding things…is to hear them talk about her," Stevenson shared. "It's helped me form an idea of her character."