MADISON, Wis. -- A Milton mother said that she's hoping history doesn't repeat itself.

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In 1984, Millie Staskal's son, Mark Staskal, stabbed his sister to death. She was 16 and Mark was 20.

Instead of prison time, he got treatment at Mendota Mental Health Institute. Staskal was released briefly to an Eau Claire group home last December, but returned to the Mendota facility.

He could now be released again, but it's a move his parents are desperately fighting and some area residents have expressed concerns about.

A judge is expected to decide on Tuesday whether or not Mark Staskal will be placed in a group home on Madison's East Side. The home is less than a block away from a Madison elementary school, Lapham Elementary School. Some parents, including Staskal's mother, said that they're worried.

"My kids come to the playground, and we take walks around," said parent William Quintanilla. "I don't let them walk by themselves, but I know there are parents that let their kids walk around freely."

Millie Staskal said that she believes her son isn't ready to leave the Mendota Mental Health Institute. He's been there for more than two decades and she said she believes he's capable of killing again, WISC-TV reported.

"I'm not against my son," Millie Staskal said. "I just don't want this disease to win again. I don't want anybody to die from it. He can be angry enough to kill. You won't see it in his face, you won't hear it in his voice, you won't see it in his eyes."

Quintanilla said the prospect of Mark Staskal's release is raising alarm bells.

"His own mother doesn't trust him. Who else? Not me as a parent with young kids," Quintanilla said. "It does concern me. I would hope that they would have some kind of restrictions for him being out on the streets. But regardless, I'm still going to be very cautious to let my kids out (and) out of my sight."

Officials with the state Department of Health and Family Services declined to comment on the case because of patient confidentiality issues, but a spokesman said that in all cases involving those with mental diseases, community safety is a high priority, WISC-TV reported.

The Madison Metropolitan School District was recently notified about the possibility that Staskal could be moving into the neighborhood. Once the final ruling is made on Tuesday, they'll decide whether or not it's appropriate to alert parents.

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