The mother of one of Christine Allen’s poisoning victims says she can’t understand what led somebody she’d known from childhood to sicken multiple children.

Allen, 32, pleaded guilty Wednesday to four counts of administering a noxious substance with intent to cause bodily harm.

She admitted to using eyedrops containing tetrahydrozoline to poison four children.

In the most serious of the cases, Allen admitted to poisoning an infant multiple times during her first four months of life – including once just hours after her birth.

The girl’s mother – who, like her daughter, cannot be identified due to a court-ordered publication ban – says her daughter has been left with serious, permanent developmental delays.

“She can’t do too many things at once. If you’re talking to her and she’s trying to eat, she’ll choke. She has to concentrate on swallowing,” she tells CTV News.

“We actually went a whole year not knowing if (our daughter) would wake up … having what we called an episode.”

Those ‘episodes’ began while the girl was still in hospital following her birth in July 2012.

During her first four months of life, she stopped breathing more than 12 times – and was in and out of hospitals, being placed on life support on seven separate occasions.

Now nearly two years old, she has significant developmental delays both physically and mentally.

At times, she has trouble walking, hearing and even speaking – problems doctors say are related to brain activity.

“Her ears can hear. If they test her ears, they can hear,” says the girl’s mother.

“The hearing problem is coming from her brain injuries – from the lack of oxygen. It slowed her processing down.”

It’s a particularly devastating turn of events for the mother because she had known Allen since the two were young children themselves.

“She was like a sister. We treated her like she was part of the family,” she says.

Initially, the mother says, she had no inkling Allen was behind her daughter’s ‘episodes’. Only after the Kitchener woman’s arrest last summer did she realize the connection.

“She got caught, and all the symptoms that she was poisoning children with were everything that (our daughter) had,” she says.

When the court case against Allen came to its conclusion Wednesday, the mother was there along with a crowd of supporters.

Other victims also sat in the courtroom with supporters of their own.

The mother of Allen’s youngest victim says she “couldn’t stop crying” as someone she once considered a friend was sentenced to six years in prison.

“It was hard to look at her, knowing that she had done that,” she says.

While it’s not clear exactly how the rest of the child’s life will be affected by the delays, her mother believes she will never be able to eat anything other than the softest of foods.

Her family currently spends $1,000 each week on pureed food, formula and therapy for their daughter.