"No way," Landgraf recalled telling a friend as she made her way to the door facing stately Loomis Street in this western Chicago suburb. "There's nothing going on."
A glance down the street proved differently. There were police cars and yellow crime-scene tape at the cranberry-red Victorian house a block away.
When police arrived last Friday, they found the bodies of 3-year-old Thomas Lemak and his 7-year-old brother, Nicholas, in their beds. Their 6-year-old sister, Emily, lay lifeless in her parents' room.
All three children had been drugged and smothered to death.
The initial shock was compounded when their mother, Marilyn Lemak, was charged with the crime. After the slayings, police said, Mrs. Lemak took several pills and cut her arm.
"She couldn't have done that in her right mind," Landgraf said. "Who could? It makes you feel so sick."
Many residents stopped Tuesday to leave flowers, teddy bears, candy canes, dolls, ceramic angels and other mementos near the three white crosses erected in the Lemak front lawn.
The murders have jolted this neighborhood of grand homes and lush lawns, honored in 1997 as the most kid-friendly city in America by Zero Population Growth, a lobbying group.
Marilyn Lemak added to that cozy image, until Friday, prosecutors say, when she called police to her home in the town's historic district.
Mrs. Lemak, a brown-haired 41-year-old, was always known as a loving mother and friend, someone who always looked "put together."
She and her physician husband, Dr. David Lemak, were in the middle of a divorce, though it seemed to be going amicably. Neighbor Tom Klingbeil said both parents were attentive and loving with their children.
Police found a wedding photograph of the Lemaks with a knife stuck through David Lemak's chest, as well as a crumpled wedding dress on the bathroom floor, the Chicago Tribune reported Wednesday.
Daniel Kuhn, a lawyer representing Mrs. Lemak in her divorce, said she appeared to be sedated and "utterly devastated" when he visited her in jail on Tuesday.
"I think people are overwhelmed and don't know how to react," said a neighbor, Edna Steinbock. "My heart aches for her. I'm praying for her and what she's going through... her own private hell. I'm not angry; I'm confused. I keep saying `Why?'"
Mrs. Lemak occasionally worked at Dreyer Medical Clinic in Aurora, filling in for nurses who were sick or on vacation, clinic spokeswoman Nancy Hopp said.
She often was seen walking or driving her children to Ellsworth Elementary School a couple of blocks from her home.
A week before the deaths, Mrs. Lemak attended a local party. A friend, who also attended the get-together, said Mrs. Lemak was uncharacteristically disheveled, but otherwise pbeat and pleasant, despite the fact that her husband had moved out a few weeks ago.
"It's like nothing was wrong," Tom Klingbeil said. "And that's what's so scary."