The parents of Siamese twin boys regained guardianship of their sons yesterday, one year after the state took custody because of accusations the couple tried to starve the infants to death.

The boys were born May 5, 1981, at Lakeview Medical Center in Danville, but eight days later the family services department took custody, saying there had been complaints that they were not being fed.

Vermilion County State's Attorney Ed Litak later charged the parents and family physician Dr. Petra Warren with attempted murder, alleging a conspiracy to starve the boys to death.

A judge dismissed the criminal charges for a lack of evidence, and a county grand jury this year heard Litak's evidence and refused to indict the three.

While in state custody, the boys were examined by specialists at Children's Memorial Hospital in Chicago and doctors concluded they could not be separated.

Thay are joined at the waist and share some organs.

". . . . I have never seen anything in their home that could give any concern for the care of Jeff and Scott," said social worker Jan Miller. "They have excellent physical care as well as emotional support from both parents."

Robert Mueller is a Danville physician, and his wife, Pamela Schopp, is a nurse. They equipped their home with oxygen devices and other equipment necessary to care for the twins.