Transcript for Major break in cold case more than four decades old
major break in a cold case more than four decades old. Two young sisters who vanished in Maryland, their bodies never recovered. And yet tonight, a guilty plea. Here's ABC's David Kerley. Reporter: For these young girls, 12-year-old Sheila, 10-year-old sister Katherine, some justice tonight. They were snatched off a Maryland mall they had walked to more than 40 years ago. All these years later, this carnival worker, a convicted sex offender, now 60, faced a judge. What is your plea to the indictment? I plead guilty to felony first degree murder. Reporter: The girl girls' parents and brothers there, thanking police and prosecutors who kept the cold case alive. They have treated Sheila and Kate as if they were their own sisters or daughters. Reporter: But there's more to this case. Lloyd Welch admits helping abduct the girls, transporting at least one body to Virginia, but denies raping or killing th. Prosecutors suggest others involved in the killings are dead or a case could not be proven. We've put one of the main perpetrators away for all intents and purposes for the rest of his life. Reporter: That's because Welch is already serving time for a separate sex crime and will be sentenced to 48 years in prison for the killing of these two young girls. David? David Kerley, thank you.
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