It was no secret that Jerry Hobbs could be mean, especially if he'd had a few belts. This was a man who once stabbed a motorist in the belly for squealing his tires. This was a guy who had chased his girlfriend and neighbors through a Texas trailer park with a revved-up chainsaw. In his 34 years, Hobbs has been arrested nearly 30 times. But even for all that, nobody could have imagined what happened on Mother's Day.

Last Sunday, his daughter, Laura Hobbs, 8, and her friend, Krystal Tobias, 9, spent the afternoon soaring on a swing set and sailing off on a bike ride in Zion, Ill. Laura did the pedaling; Krystal stood on the rear pegs. Hobbs was angry that Laura's mom had suspended her grounding punishment--she had sneaked some money from her mother--and let her go out to play. So he went out to find the girls. "Come home now!" he demanded. When his daughter apparently defied his order, Hobbs, prosecutors say, became enraged. The next morning, the bodies of the two little girls were discovered in the woods near Beulah Park. Authorities say Hobbs confessed to the killings. The faces of the girls were bloodied and beaten. Laura was stabbed 20 times, including once in each eye. Krystal was stabbed 11 times. The brutal slayings shocked and sickened this working-class town, about 50 miles north of Chicago. "In a case like this," said Michael Waller, a prosecutor in Lake County, "the traditional attribution of a motive doesn't even apply."

Hobbs is not married to Laura's mother, Sheila Hollabaugh. But court records indicate he tormented Sheila for much of their 10-year relationship. "Every time he comes around, he starts some kind of fight with me," Hollabaugh wrote in a court paper for an order of protection from Hobbs in 2001. "If I listed the dates, it would be every other day." After the chainsaw attack--he was subdued by a shovel-wielding neighbor--Hobbs was sentenced to probation, as long as he attended anger-management classes. He did not, and was sent to a Texas prison for 18 months. From prison he corresponded with Hollabaugh. When he was released last month, she let him come to Zion to live with her and their three children--she also has a child from another relationship--and her parents.

According to prosecutors, Hobbs told police that Laura's mother was being too lenient with Laura. He told authorities he intended to impose some discipline on the carefree girl. When his daughter resisted going home on Mother's Day afternoon, police say Hobbs told them he punched her twice in the face. Krystal came to her defense--a 60-pound girl battling the six-foot-tall man. Hobbs told police that Krystal pulled a knife on him--prosecutors don't believe the girl had a knife--and that he took it away. The knife has not been recovered. After he stabbed them to death, Hobbs told police he dragged them about 20 feet to a wooded section, then went home and tried to clean himself with rubbing alcohol. After an all-night search, it was Hobbs who led police to the bodies. Under questioning, he acted suspiciously, and soon confessed. He is being held without bond in Lake County Jail.

Groups of people stood vigil in front of Laura's and Krystal's modest homes last week, praying, weeping and singing "Amazing Grace." Krystal's half brother, Alberto Segura, 15, said his sister has gone to heaven, "but our family is in hell." Krystal and Laura had been nearly inseparable. They were in the same second-grade class. Whenever they could, they would have a sleepover, and collaborate on projects. Krystal was the artist; Laura the writer. They were pals to the very end.