The truck driver, a 59-year-old man from Western Australia, was charged on Monday with two counts of dangerous driving causing death.
Tributes have flowed for Ms West and Deighton as the tight-knit community grapples with the loss.
The family are from Epsom, a suburb of Bendigo.
Ms West was a teacher at Strathfieldsaye Primary School, where Oakley is a student. Deighton was due to start there next year.
The school’s principal Cindi Bruechert has sent a letter to the grieving community about the tragedy.
“Both Jess and Deighton died and other members of her family, her husband Anthony and eldest son Oakley, were injured,” Ms Bruechert wrote.
“I have spoken with Jess’ extended family members and offered them the heartfelt sympathy of our whole school community, as well as any support or help we are able to give.”
Jess Eagle, a swimming teacher at Just Keep Swimming Swim School in Bendigo, said she taught Deighton for about a year and had got to know Ms West as a “doting mum” who was always encouraging her sons.
“Jess was very bright and bubbly, always came in with different coloured hair, each week that she came in. She was very encouraging and very proud of the things he was achieving,” she said.
“She was the type who would do anything for anybody, happy go lucky. You could see that in Deighton and Oakley, they were both happy kids.
“She was looking forward to spending holidays in the pool teaching Deighton a few more things before he started school,” she said.
Ms Eagle also described Deighton as “the happiest kid” who was “independent in his ways”.
“He used to pack his own bag to swimming – a couple of times he only packed a pair of dacks and that’s what he wore home,” she said.
“The last time [we saw him] he actually packed his school clothes, he had just got them that morning or the day before, packed them to wear home to swimming. He was so excited to get to school, he even had his school hat on.”
“He never came to swimming upset or angry, he was literally always happy. He always did what he was asked and always had a smile on his face when doing it. He was always willing to try everything and was so proud of himself when he achieved different goals.”
She said the community were now working out ways to help support the family.
“This has affected so many people … it is hard on the parents, seeing their kids going to enjoy the first day of prep knowing Deighton can’t enjoy that,” she said.
“In the blink of an eye things can change so quickly.”
Other friends and family have also taken to social media to remember the pair.
One friend said that for Ms West, her husband and sons were “her world”.
“I know Mummy will keep you safe in heaven,” the friend wrote.
Another relative wrote that “nothing will ever be the same again” following the tragedy.
“My heart has been broken into a million pieces and it hurts so much,” she wrote.
There has been 263 lives lost on Victorian roads so far this year, compared to 212 this time last year.
Simone is a crime reporter for The Age. Most recently she covered breaking news for The Age, and before that for The Australian in Melbourne.