What is the story of the Radely Place and the radelys

From the text;

"The Radley Place jutted into a sharp curve beyond our house. Walking south, one faced its porch; the sidewalk turned and ran beside the lot. The house was low, was once white with a deep front porch and green shutters, but had long ago darkened to the color of the slate-gray yard around it. Rain-rotted shingles drooped over the eaves of the veranda; oak trees kept the sun away. The remains of a picket drunkenly guarded the front yard "swept" yard that was never swept-where johnson grass and rabbit-tobacco grew in abundance.

Inside the house lived a malevolent phantom. People said he existed, but Jem and I had never seen him. People said he went out at night when the moon was down, and peeped in windows. When people's azaleas froze in a cold snap, it was because he had breathed on them. Any stealthy small crimes committed in Maycomb were his work. Once the town was terrorized by a series of morbid nocturnal events: people's chickens and household pets were found mutilated; although the culprit was Crazy Addie, who eventually drowned himself in Barker's Eddy, people still looked at the Radley Place, unwilling to discard their initial suspicions. A Negro would not pass the Radley Place at night, he would cut across to the sidewalk opposite and whistle as he walked. The Maycomb school grounds adjoined the back of the Radley lot; from the Radley chickenyard tall pecan trees shook their fruit into the schoolyard, but the nuts lay untouched by the children: Radley pecans would kill you."