A Philadelphia forensic pathologist told a Common Pleas Court jury Tuesday that a 2-year-old Rhawnhurst boy would almost certainly be alive had he received routine medical care before he died last year of pneumonia.

"This type of pneumonia, this type of bacteria, is preventable through vaccination and treatable with antibiotics," testified Assistant Medical Examiner Edwin Lieberman, referring to the disease that killed Kent Schaible in January 2009.

Lieberman defended his decision to classify the death as a homicide as a prosecutor began her involuntary manslaughter case against the boy's parents, Herbert and Catherine Schaible.

There is no mandatory prison term for involuntary manslaughter, but the Schaibles each could face up to 24 years in prison if convicted.

The Schaibles are members of a church that preaches forgoing medical care in favor of prayer and faith healing. Authorities allege that when their son became ill with fever, cough, diarrhea, and loss of appetite, the Schaibles cared for him at home for almost two weeks, praying for him to get well as he died.

It's a case in which the jury must discern the boundaries of parental responsibility, religion, and the law.

"A 2-year-old doesn't have the wherewithal to say, 'Mommy, Daddy, I'm sick. I need to go to a doctor,' " Assistant District Attorney Joanne Pescatore said in her opening statement.

"A simple visit to the doctor, a prescription, and that little boy could have been with us today," Pescatore said.

The Schaibles' attorneys, however, argued that it took an autopsy to determine what killed young Kent and that the symptoms his parents saw were not different from those of cold or flu. The Schaibles, their lawyers told the jury, are on trial because of their beliefs.

"If we don't get through the emotion, we will never get to the reason that this child passed away," said Bobby Hoof, the attorney for Herbert Schaible, 42. "We are not here to discuss religion, we're here to discuss why this child passed away."

Hoof said he would bring in his own expert forensic pathologist, the celebrated Pittsburgh medical examiner Cyril Wecht, who will testify that the bacterium that killed Kent - Haemophilus influenzae Type B - is resistant to antibiotics.

"It would not have cured the child," Hoof added. "The child would have died."

Mythri Jaraman, the lawyer for Catherine Schaible, 41, argued in her opening statement that Schaible's religion is irrelevant because the prosecution cannot prove a key element of involuntary manslaughter: that she knew or should have known Kent "faced a substantial risk of death."

"Not this D.A., not Mr. Hoof, not the state and not any one of us loves Kent Schaible any more than his mother," Jaraman told the jury.

No one has alleged that the couple are anything but loving parents. Both defense lawyers said visits to the Schaible house after Kent's death by a nurse and social workers showed no signs of neglect or abuse among the couple's six other children.

Both Schaible lawyers argued that the couple - both quit school after ninth grade - cannot be expected to know when cold and flu symptoms are life-threatening pneumonia.

Catherine Schaible's mother, Mary Wakefield, testified that her daughter told her Kent was "coming along, doing good."

When she saw Kent on Jan. 24, 2009, Wakefield testified, he seemed grumpy but otherwise healthy. She said she was shocked when Pastor Ralph Myers, assistant pastor of the First Century Gospel Church, came to the house to pray with the parents and she was told the child had died.

First Century Gospel Church, founded in 1925, is at 4557 G St. in Juniata Park.

This is not the first time the church and its members have run afoul of the law over its belief in faith healing.

In 1993, Philadelphia officials got a court order against another couple after they prayed over their 12-year-old son at home instead of taking him to an emergency room after he was hit by a car and seriously injured.

And in 1991, the church and another congregation, Faith Tabernacle of Nicetown, came under scrutiny after eight children died in a measles epidemic after members resisted vaccinating their children.

Contact staff writer Joseph A. Slobodzian at 215-854-2985 or jslobodzian@phillynews.com.