Nathan Dumas was found injured at a home Friday and died in hospital the following day. Niagara police are on the hunt for Kuijer, a 43-year-old Ontario man wanted in connection to a stabbing at a bank and linked to the investigation of his stepson's death.
Police originally reported the stabbing as a violent bank robbery at an RBC branch, but Gavin clarified on Sunday that it wasn't a robbery or a domestic dispute.
"I said to him, 'Well let's go inside and talk about arrangements for our kids.' We have three kids", Dumas said in an interview with The Standard. "We are asking anyone who has information about Mr. Kuijer to call 911".
Police also secured a building at 173 Queenston Street Friday that is listed in the phone book as the residence of Kuijer.
Her son's death has been a blow to their community, in the heart of Ontario's wine country, Gavin added.
The search continues for a St. Catharines man accused of killing his stepson and attempting to murder a bank employee.
The boy died at St. Catharines hospital Saturday morning.
Police described Kuijer as armed and risky.
"The community is upset and grieving", said Kim Yielding, a spokesperson for the District School Board of Niagara.More news: English Premier League club Middlesbrough sack manager Aitor Karanka
Police say Whitney Dumas "is co-operating with [the police] and [they] have taken security measures to ensure her safety".
Police later said they believe the victim was targeted but were still trying to determine the motive for the attack.
Initially treated at the St. Catharines site of the Niagara Health System, the woman was transported to a trauma centre outside of the Niagara region.
The man fled the scene in what is believed to be a 2009 Pontiac Montana minivan, licence plate BYTE 392.
As of Monday, the boy's stepfather, 43-year-old Justin Kuijer, remained at large.
Authorities said the suspect's vehicle also has a floral tribute sticker in relation to missing person "Ashley Simpson" on the rear driver's back window.
Kuijer is described as white with a thin build, trimmed beard and longer dark hair.
Kuijer was last seen wearing an orange hoodie under a brown leather coat, dark trousers, a black toque, and boots, police said. A sign on the RBC door said it would reopen Monday.
When he was last seen, police said Kuijer was wearing an orange hoodie under a brown leather coat, dark trousers, a black toque, and boots.