Sky Walker couldn't tell his mother if he loved her. Or why he liked "The Price is Right."
But Getrude Steuernagel was devoted to her son, nonetheless, even when their world shrank as Walker's severe autism seemingly cut them off from many aspects of a normal life.
Now, Walker, 18, is sitting in a jail cell, accused of beating his mother to death, while her friends and family members struggle to understand why -- an answer that may never come.
"There really weren't any clues in the house," Molly Merryman, a friend and Kent State University associate professor, told ABCNews.com. "I think it's always something we'll wonder about and never know."
Steuernagel, a political science professor who had penned opinion pieces on her son's autism for the university's Daily Kent Stater, was found severely beaten in their Kent, Ohio, home Jan. 29 after university employees called police when she failed to show up for work.
Portage County Sheriff's Office Major Dennis Missimi said Steuernagel, 60, was found on the kitchen floor. Walker was in his room.
"They approached him. There was a slight scuffle that ensued when he was taken into custody," Missimi said of Walker's arrest.
Errol Can, an attorney in Kent who has been hired to represent Walker, said he had no comment on his client's case.
Rushed to the hospital, Steuernagel died Friday without regaining consciousness.
Summit County Medical Examiner Investigator Gary Guenther told ABCNews.com that the office was still waiting for medical records and tests on tissue samples before ruling on Steuernagel's cause of death. But Monday's autopsy revealed "multiple bruising" on her head and chest as well as brain trauma.
Initially charged with attempted murder along with assault on a police officer, Missimi said he expects Walker's charge to be upgraded to murder. The police officer he allegedly assaulted was kicked in the face and has returned to work.
Living With Sky
By Steuernagel's own writings, life with Walker was not an easy one. She mused about becoming more and more isolated as her son got older and friends began to shy away from sending invitations to weddings and parties.
And they seemed not to understand her life, nor she theirs.
"I had no patience with good and decent colleagues who told me how busy they were," she wrote in a March 2008 opinion piece for the Stater. "Busy? Try spending an evening sitting in a closet with your back to the door trying to hold it shut while your child kicks it in."
Merryman said that Steuernagel -- known to everyone as "Trudy" -- wasn't interested in candy-coating the reality of living with a severely autistic child. And her life was not an unhappy one.
Merryman said Steuernagel and Walker would eat dinners together and socialize at Merryman's farm where Walker would delight in taking walks and sneaking her Weimaraner forkfuls of pasta.
"He was never much on communicating, but we would have a lot of fun together," she said.
Steuernagel wrote that she began to look for joy in their lives no matter how small or inconsequential it may have seemed to the outside world -- vanilla ice cream, a TV game show or even the few minutes of peace she got while Walker put on his shoes.
"I realized I had approximately 17 seconds where I could lie back and not have to do anything, fear anything, clean anything, teach anything," she wrote in the March 2008 piece. "Seventeen seconds it took for Sky to jam his feet into his shoes, sit back on the chair and put his legs on my lap. Some days, those were the only blissful 17 seconds in my day, but they sustained me."
Merryman said Walker was diagnosed at about 2 ½ with severe spectrum autism. He didn't speak much, but would say certain words often like "Mommy" and "good." Mother and son had their own language, she said. While Walker would say things that didn't make sense to an outsider, his message was perfectly clear to her.
But as he got older, Walker became more and more withdrawn. Leaving his comfort zone became increasingly difficult, Merryman said. And at 18, Walker was both taller and heavier than his mother.
Lori Warner, a licensed psychologist and director of the Hands-On Parent Education Center for autism families at Beaumont Hospitals in Michigan, said living with children, especially teenagers or adults, with low-functioning autism is a high-stress environment where parents have to be on alert at all times.
"For them, I think it's almost like a war zone," Warner told ABCNews.com. "It's almost like they are on eggshells.
But Warner said the act of an autistic child murdering his or her parents is "incredibly rare."
"I've never heard of this happening before," she said. "These are not typically violent people."
Warner, who has not treated Walker, said autistic teenagers present a whole new challenge for parents. No longer can they pick them up like they could a screaming 2-year-old.
And when that child becomes bigger than the parent, tantrums that are so common for so many can become dangerous.
"For some of the kids, they're just flailing and upset and they're just striking out at whatever's around them," she said. "Other kids are aggressing toward specific people."
But trying to know whether autistic children understand the consequences of their violent outbursts is something parents may never figure out.
And, Warner is quick to point out that not all autistic children hit or throw violent tantrums. But, she added, low-function autistics "don't have any way to tell you what they want other than their behavior."
Merryman said she had asked Steuernagel if she was afraid of her son and she said no.
"When Sky would get upset he would do things like say 'Mommy go,'" Merryman said. Steuernagel would leave and Walker would be able to calm himself down.
Merryman said Steuernagel's family will now take over guardianship of Walker and have plans to advocate on his behalf as his case winds through the justice system.
For now, Walker will stay in the jail with bond set at $2 million. And for the boy who loved to run around Merryman's farm, being locked up in an unfamiliar place without any understanding of why must be wrenching.
Kent State University has plans for a memorial service in Steuernagel's honor Friday. Merryman said she was one of the most popular professors on campus who relished sitting in her office with students sprawled out on her overstuffed chair, noshing on candy.
But she was always "Sky's mom" ahead of being Dr. Steuernagel. Even though Walker would never be able to achieve what her students had, Steuernagel delighted in what he could do.
"Trudy wouldn't have traded any of those bad moments at all," Merryman said, "for being Sky's mom."