Steven Gregory Stayner (April 18, 1965 – September 16, 1989) was an American kidnapping victim and the younger brother of serial killer Cary Stayner. On December 4, 1972, seven-year-old Stayner was abducted in Merced, California, by child molester Kenneth Parnell. He was held by his abductor 38 miles (61 km) away in Mariposa County, and later in Mendocino County, until he was aged 14, when he managed to escape with another of Parnell's victims, five-year-old Timothy White.

Steven Stayner was the third of five children born to Delbert and Kay Stayner in Merced, California. He had three sisters and an older brother, Cary. In 2002, Cary was convicted and sentenced to death for the murders of four women near Yosemite National Park.

On the afternoon of December 4, 1972, Stayner was approached on his way home from school by a man named Ervin Edward Murphy, who had become acquainted with convicted child molester Kenneth Parnell as co-workers at a resort in Yosemite National Park. Murphy, described by those who knew him as a trusting, naïve and simple-minded man, had been enlisted by Parnell (who had passed himself off to Murphy as an aspiring minister) into helping him abduct a young boy so that Parnell could "raise him in a religious-type deal," as Murphy later stated.

Acting on instructions from Parnell, Murphy passed out religious tracts to boys walking home from school that day and, after spotting Stayner, claimed to be a church representative seeking donations. Stayner later claimed that Murphy asked him if his mother would be willing to donate any items to the church. When the boy replied that she would, Murphy then asked Stayner where he lived and if he would be willing to take Murphy to his home.

After Stayner agreed, a white Buick driven by Parnell pulled up, and Stayner willingly climbed into the car with Murphy. Parnell then drove a confused Stayner to his cabin in nearby Catheys Valley instead. Unbeknownst to Stayner, Parnell's cabin was located only several hundred feet from his maternal grandfather's residence.

Parnell molested Stayner during the first night at the cabin. He began raping the boy 13 days later, on December 17. After Stayner told Parnell many times during that first week that he wanted to go home, Parnell told Stayner that he had been granted legal custody of the boy because his parents could not afford so many children and that they did not want him anymore.

Parnell began calling the boy "Dennis Gregory Parnell", retaining Stayner's real middle name and his real birth date when enrolling him in various schools over the next several years. Parnell passed himself off as Stayner's father, and the two moved frequently around California, living in locations including Santa Rosa and Comptche. Parnell allowed Stayner to begin drinking at a young age and to come and go virtually as he pleased. As he frequently moved from one menial job to another, some of his work required travel and leaving Stayner unguarded. An adult Stayner later remarked that he could have easily used these absences as opportunities to flee, but was unaware how to summon help.

Parnell gave Stayner a Manchester Terrier that he named Queenie. This dog had been given to Parnell by his mother, who was not aware of Stayner's existence during the period when he was being held by Parnell.