PORTAGE, Wis. -- A pediatrician testified on Monday that the 11-year-old boy found tortured at a Portage house was the most beaten child that she's ever seen that was still living.

Dr. Barbara Knox from University of Wisconsin Children's Hospital said that the boy was in grave condition when he arrived at the emergency room on June 14.

Knox said that he was "profoundly malnourished" and had pneumonia. He had burns, bruises and scars all over his body. The pediatrician testified that the boy looked like a "concentration camp survivor." Several of his fingertips and three toes had to be amputated because they were burned so badly.

The boy was allegedly being kept in a locked closet in the home, WISC-TV reported.

The testimony came during a preliminary hearing for Candace Clark and Michael Sisk. They're accused of torturing the boy, killing his mother, Tammie Garlin, and burying her in the back yard of the house that they were renting in Portage.

Prosecutors dropped a charge of party to murder and hiding a corpse against Michaela Clerc. She agreed to waive her preliminary hearing, but she still faces other charges.

A Columbia County judge will decide whether there's enough evidence against Clark and Sisk to hold them for trial.

The three are accused of torturing Garlin's son, burning him, whipping him and locking him naked in a closet.

The boy's sister, 16-year-old Felicia Garlin, was initially charged with murder and child abuse along with Sisk, Clark and Clerc, but charges against her have been moved into juvenile court.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.