An Arlington woman and purported mail-order bride from Russia who was accused of killing her husband’s 8-year-old son and his ex-wife pleaded guilty to two counts of capital murder Tuesday morning, according to prosecutors.

Natalia Wilson, 50, will serve two consecutive life terms without the possibility of parole, said Prince William Commonwealth’s Attorney Paul Ebert. He said prosecutors and Wilson’s attorneys reached the deal – ruling out the possibility of the death penalty – on Friday and scheduled the hearing early Tuesday.

The plea agreement was accepted by Judge Craig D. Johnston, Ebert said.

Slavka P. Naydenova, 41, and her son, Paul A. Wilson, 8, were fatally stabbed in February 2010 in Naydenova’s Dale City home, according to police. The bodies were discovered by Naydenova’s current husband.

Ebert said that Wilson, of the 1900 block of Columbia Pike in Arlington had become jealous of the relationship between Naydenova and her husband, Lester Wilson. Authorities think the boy was killed after he tried to come to the aid of his mother, Ebert said. His body was found on top of hers.

Ebert said that the case “had some definite legal issues that might have taken many years to iron out” if prosecutors pursued the death penalty. One of the major issues was the more than 20-hour interrogation of Wilson by Prince William police.

Defense attorneys had argued in pre-trial motions that Wilson’s confession should be thrown out because of what they deemed were coercive interrogation tactics — along with problems with translation of the interrogation — but a judge overruled those concerns and said the court would allow the confession and what Wilson said in a videotaped interrogation.

One of Wilson’s attorneys did not immediately return a call for comment Tuesday.