'American Sniper' Widow Taya Kyle Recalls Moment She Told Kids Chris Kyle Was Dead

— -- Millions of people know the name of former Navy SEAL Chris Kyle, the most lethal sniper in U.S. history, whose story was portrayed in the blockbuster movie, "American Sniper."

Now his wife and veteran family advocate Taya Kyle is opening up for the first time in an exclusive interview with ABC's Robin Roberts about their life together and how she and their family are moving forward after Chris and his friend Chad Littlefield were murdered at a Texas gun range in 2013.

The interview will air in a special edition of ABC News' "20/20" on Friday, May 1 at 10 p.m. on ABC.

In her interview with Roberts, Taya Kyle recalled the difficult moment she had to tell their two young children that their father had been killed.

"I remember just closing my eyes, the tears rolling down and me just trying to breathe," Kyle said.

Former Marine Eddie Ray Routh was convicted of capital murder on Feb. 24, 2015, in the shooting deaths of Chris Kyle and Littlefield. He received an automatic life sentence without the possibility of parole. Taya Kyle was a constant presence at the widely publicized trial.

During their interview, Kyle talked with Roberts about her relationship with Chris through the years, and she joked that she never thought she would marry "a cowboy," but that falling in love with him "was exciting."

"I never probably thought a cowboy would want me," she said. "[And] I said I would never marry somebody -- a SEAL either. So… 'there you go with your plans again,' right?"

In the wake of her husband's death, Taya Kyle wrote a memoir, "American Wife: A Memoir of Love, War, Faith and Renewal," which details their story, how she dealt with Chris's death and her life as a military spouse. The book will be released on Monday, May 4, in collaboration with Jim DeFelice and published by William Morrow Publishers.