A two-year-old child is the latest fatality in a Hamilton fire over the weekend bringing the death toll up to five, investigators said Sunday.

The child, identified as Ella Denhollander-Hanigan, succumbed to her injuries in hospital late Saturday night. She was one of seven people who lived at the Broadway Avenue home.

The child's mother Melissa, 22, and two sisters, four-year-old Emma and one-year-old Alana, were pronounced dead Saturday morning at the scene.

"She was a good mother, this shouldn't have happened," said Melissa Denhollander's mother Patti Dixon in a tearful interview with CTV Toronto.

A 19-year-old male resident also died in the blaze. Police are withholding his identity until they notify his next of kin.

All five victims died from smoke inhalation.

Melissa's 28-year-old boyfriend Richard Griffin remains at Hamilton General Hospital where he is being treated for smoke inhalation and burns. He reportedly escaped the flames by jumping out of a second-storey window. A 20-year-old woman who also lived at the home has been released from hospital after receiving treatment.

Investigators said at a news conference Sunday afternoon that they found no evidence of a working smoke alarm at the home.

Jim Kay of Hamilton Emergency Services said the deaths have been devastating to not only the community but also to emergency personnel. He said he hopes the weekend tragedy will make people understand the importance of having working smoke detectors.

"My emotions have gone from being sad to, frankly, mad because this shouldn't be happening at this day and age," he said.

"We live in a time where people have become complacent," Kay continued. "We're hoping people will get the message and the lives that were lost here will not be in vain."

Kay said the cause of the fire is still being investigated.

"Clearly, we don't know all of the circumstances. Right now, we have more questions than answers," he said. "Our objective is to find out everything we can. We don't understand how the fire spread so quickly."

The fire broke out at 2:40 a.m. Saturday. About 20 firefighters were called to the single-dwelling home near McMaster University. When they arrived, the home was fully engulfed in flames.

Several witnesses said they heard children crying inside the house and a woman pleading for help, suggesting the mother ran back inside the house to try to save her kids.

"There was a lady and she was screaming, 'My babies are trapped inside, my babies are trapped inside,'" one man told CTV Toronto.

Dixon said her life has been shattered since her daughter and three grandchildren were killed.

"You feel as if a part of your body has been taken away, you're not whole anymore," she said through her tears. "To take one thing away from you, but to take four...four innocent people."

Pierre Yelle of the Ontario Fire Marshal's Office noted there have been four fatal fires in Ontario this weekend. Eight people in total have died.

He said families need an escape plan as well as a working smoke detector to increase their chances of surviving a fire.

"It's just not fair," said Amanda Dixon, the victims' sister and aunt, breaking down in sobs. "I wish we could just turn back time and somehow fix it all."

Just a week ago, a house fire in Toronto killed a 44-year-old father, his five-year-old daughter and his four-year-old son. The man's wife and their two-year-old daughter managed to escape.

With a report from CTV Toronto's Chris Eby