Three adults and a 15-year-old girl were charged Wednesday in connection with two shocking discoveries police made when they found a missing 2-year-old: a severely burned and blood-streaked 11-year-old boy, and the body of his mother, buried in the back yard.

The girl charged, Felicia Mae Garlin, is the sister of the boy and daughter of Tammie Garlin, whose body was found Friday.

Police believe the 36-year-old was strangled and may have been physically abused. Her daughter described how her mother was put alive in the trunk of a car as she and Candace Clark drove to Wal-Mart to buy the shovel that was used to bury her the next day, police said.

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Charged with being a party to first-degree intentional homicide are Clark, 23; Michael Sisk, 25; Michaela Clerc, 20; and Felicia Garlin. They also are charged with hiding Tammie Garlin's body and abusing the 11-year-old.

Bail was set Wednesday at $500,000 for Garlin and $350,000 for Clerc. Bail was denied for Clark and Sisk, whom Columbia County District Attorney Jane Kohlwey called the leaders of the group.

Attorneys for the defendants argued they deserved reasonable bail, saying the allegations in the complaint are unproven and they don't have the money to flee.

But Judge Alan White said the suspects used multiple aliases and have no ties to Wisconsin. Sisk was captured at a Milwaukee bus station the day after police went to his house, the judge noted.

Clark is the mother of the 2-year-old girl, who was reported missing from foster care in Florida in January. No charges have been filed in the girl's disappearance.

Authorities found the young girl and the 11-year-old boy June 14 at a rental house in Portage, about 40 miles north of Madison. They found Tammie Garlin's body a day later; an autopsy concluded that she likely died of strangulation.

The criminal complaint, citing statements from some of the defendants, says Tammie Garlin died around June 4 after they repeatedly kicked her and dropped her on her head when they were moving her to the bathroom.

The complaint said Clark and Sisk were boyfriend and girlfriend and Clerc and Tammie Garlin were lovers for five years. Clerc was angry because she thought Tammie Garlin had cheated on her, the complaint alleged.

The 11-year-old told authorities that the four would tie his hands behind his back and his legs together, then put him in the bathtub where they would run scalding hot water over him and threatened to drown him, the complaint said. He said his sister laughed as she burned him, according to the complaint.

The boy also said he was choked, punched, kicked and whipped. He said he was typically forced to get naked and was locked in a closet in his sister's bedroom, where he slept.

Kohlwey said the group apparently was making a living by stealing people's identities and using them in financial fraud schemes. Detectives said they may have victims across the country.

Investigators found multiple $500 money orders in the house made out to the group's aliases, Kohlwey said. Authorities were still unsure where the money orders came from, she said.