Teenager Kim Edwards convinced her boyfriend, Lucas Markham, to help her kill her mother and sister in their sleep at their home in Spalding, Lincolnshire.
The identities of the pair, who were just 14 at the time and are believed to be Britain’s youngest double murderers, was not reported during their trial last year, but restrictions on naming them have now been lifted by three judges at the Court of Appeal.
Edwards and Markham have been jailed for a minimum of 17-and-a-half years each for the “brutal executions” of Elizabeth Edwards, 49, and her 13-year-old daughter Katie.
Both were stabbed in the neck by Markham with a kitchen knife.
The pair spent the 36 hours after the killings having sex, sharing a bath and watching the Twilight films.
The ban on naming the pair was lifted by Sir Brian Leveson, Mr Justice Blake and Mr Justice Lewis.
Sir Brian said: “In the circumstances of this case, notwithstanding that the appellants are only 15 years of age, we have no doubt that the lifting of reporting restrictions is in accordance with law, pursues a legitimate aim and is a reasonable and proportionate measure.”
He added that the naming allowed “the full facts and circumstances” of the case to become public.
Sir Brian said the pair were “besotted with each other” and unhappy in their family homes.
Edwards bore grudges towards her mother and sister which Markham came to share, leading them to “jointly” decide to kill Mrs Markham and “entirely innocent” Katie.
The plot was apparently hatched in a McDonald’s.
Sir Brian said: “The reality is that anonymity lasts only until 18 years of age and both appellants face a very considerable term of detention that will stretch long into their adult life.
“The process of reflecting on their dreadful crimes, addressing their offending behavior and starting a process of rehabilitation will be a lengthy one.”