In the Criminal Code of Canada, the offence is the awkward "failing to provide the necessaries of life," and it has come to mean that the failure must be a stark departure from what a reasonably prudent parent would do in circumstances where death or serious harm to the child was a predictable result.
The Sergio Fernandes definition is much more succinct: "I didn't know how serious it was. If I did, I would have grabbed my son and went to hospital, like any normal person would do."
But Mr. Fernandes, who was testifying Thursday at his former common-law wife's manslaughter trial via video link from Portugal, didn't know.
When he left for work early on the morning of Sept. 11, 2007, he left his two small boys behind with their mother, Melissa Alexander.
When he arrived home about 13 hours later - knowing only what his wife had told him, that the baby, 18-month-old Miguel, had had a "little incident" and received a minor burn to his leg - Miguel was in his crib.
When Mr. Fernandes went in to check on him and began to unzip his onesie to have a look at the injury, Ms. Alexander dissuaded him, said "not to pester him right now, he would start moving and crying again and it would take forever to quiet him down."
Mr. Fernandes, now 26, had a shower and got the dust and grime from his bricklaying job off him. He had dinner. He bought and smoked some weed on the balcony. He peeked in a couple of times on Miguel, once offering him his bottle, which the baby didn't take.
His eyes were open then, but he was very still, very quiet.
Mr. Fernandes peeked in a couple more times, but Miguel was still in the same position, though now his eyes were closed, and his big brother, almost three-year-old brother Shawn, was asleep.
Had he undone that zipper, Mr. Fernandes would have seen the catastrophic injuries to the lower half of the wee boy's body - the "full thickness" (meaning, to all layers of the skin) burn to every centimetre of his legs but for the tops of the toes and the fronts of both knees, and to most of his back and bum; the swelling and blisters; the places where Ms. Alexander had applied a white cream and cotton batting dressing.
She told him not to look, not to bother the baby. "Why I didn't," Mr. Fernandes said, "it's a question I ask myself every day."
As it was, a few hours after he kissed Miguel and Shawn goodnight, Mr. Fernandes woke to a lot of noise in the small Jane Street apartment. There were firefighters and cops in the living room and, working over Miguel, paramedics.
"After everybody was inside of my home," he told Ontario Superior Court Judge Anne Molloy, who is sitting without a jury, "I knew what happened because he [Miguel]didn't have his onesie on any more." Until that moment, he said, "I knew it was a burn, of course, but I never knew it was anything like what I saw in my living room."
Mr. Fernandes didn't realize Miguel already was, in emergency lingo, vital signs absent. His blood vessels had begun to leak and lose fluid - this is hypovolemic shock, meaning the blood volume has shrunk. As Howard Clarke, a plastic surgeon at Toronto's Sick Children's Hospital and a burn expert who testified at trial put it, this was "a very large burn in a very small child" and what happens in such cases is that they lead to "ever-diminishing blood pressure, ever-increasing pulse rates trying to make up for that, but eventually the blood pressure will fall low enough so that the major organs are not perfused appropriately with blood," and stop working.
Miguel was rushed to hospital - first responders never give up easily with children - where death was formally pronounced a little later.
At some later point presumably - Mr. Fernandes wasn't asked about this - he would have learned that some time after Miguel was burned, Ms. Alexander left the two boys alone and went shopping. One was dying; the other was there to witness and suffer it.
Receipts recovered in the apartment, where Miguel's skin was found in garbage cans, showed the now 25-year-old mother was out and about, buying a few things at a nearby Canadian Tire, a No Frills, an HMV store.
"It is clear that Ms. Alexander left the apartment, after Miguel had been burned, to go shopping without the children," Crown attorney Barry Stagg said in his closing statement.
Mr. Stagg pointed to Dr. Clarke's evidence that Miguel would have been inconsolable with pain as a possible explanation for her leaving - to escape his cries.
It wasn't until 2.25 on the morning of Sept. 12, by her own account at least 10 hours after Miguel was hurt, that Ms. Alexander phoned 911 to report that her little son was dead.
She blamed him, of course, just as she had when she told Mr. Fernandes about the "little incident". She'd had a bowl of hot water on a table, for crimping her hair, and he'd pulled it down onto himself.
Dr. Clarke testified, however, that Miguel's injury was what's called "an immersion scald" one, meaning he had likely been placed in a tub of hot water.
Ms. Alexander's hair was beautifully crimped in court, I could not help but notice.
Judge Molloy will hear closing arguments from defence lawyer Catherine Currie Friday.