The disappearance of Katherine and Sheila Lyon in 1975 shocked the nation, and particularly Maryland. Investigators were haunted by it, and their parents were destroyed.
Lloyd Welch, a 60-year-former carnival worker entered the plea in court 42 years after the disappearance.
Welch was sentenced to 48 years in prison as part of a plea agreement with prosecutors. He's currently serving time in Delaware for sexually abusing a 10-year-old girl; his sentence there ends in 2026 at which point he will begin his new sentence.