A Toronto court heard closing arguments Friday in the trial of Melissa Alexander, a 25-year-old woman charged with manslaughter after she allegedly delayed taking her badly burned toddler to a hospital.

Alexander had worked with children for years at a community centre and had taken a first aid course, but did not call 911 when her son Miguel was badly scalded in September 2007.

Instead, she is accused of leaving the 19-month-old in her apartment with her three-year-old and while she went shopping for CDs. It was more than 10 hours before she called 911, but by then it was too late for medics to save her son.

Alexander claims Miguel spilled hot water on himself, while doctors testified that it's more likely he was placed in exceeding hot water.

On Friday, her manslaughter trail wrapped up with closing arguments from the defence. Alexander wept in court as her lawyer defended her care of her son, but Justice Anne Molloy was critical of Alexander's version of events.

"Let's just get the elephant out, shall we? She said the child poured water all over himself… That is not what happened, it is not physically possible," said Molloy. "That is plain as the nose on your face."

Defence lawyer Catherine Currie shot back, saying that the trial was not about how the child was burned, but whether his mother waited too long before seeking help.

Currie said the burns killed the boy, not the delay, admitting the first aid her client applied -- Vaseline and Polysporin -- was obviously not adequate. In hindsight, the child should have been immediately taken to hospital, Currie said.