Ellie Hunt, nine and Oscar Hunt, five, who were pupils at Rockingham Junior and Infant School, died on August 24 following the accident, which happened at around 8pm near Jinnah Restaurant and involved a white HGV and a grey motorhome.
Their mother Shirley Anne Hunt, 44, also died in the collision on the A64 near Flaxton in North Yorkshire.
The road was closed between Barton le Willows and Flaxton for several hours while emergency services worked at the scene.
The children’s father, Craig, and six-year-old brother, Brooklyn, survived the crash, but returned home to find their home had been burgled.
Roads policing Sergeant Paul Cording, of North Yorkshire Police, was moved to set up a fundraising page to replace some of the items taken, which included an Xbox, TV and other sentimental items.
The GoFundMe page has so far raised £20,021.
Sgt Cording said: “Unbelievably though when the young lad and his dad returned home they found their house had been burgled and the thieves had taken everything, including items such as an a TV, Xbox and sentimental things that can never be replaced.
“Myself and my team, along with other 999 colleagues, are horrified with what has taken place and can’t just sit by and do nothing.”
A statement from Rockingham Junior and Infant School, and Willow Tree Academy Trust said that the school community had been in “shock”, and paid tribute to the “kind” youngsters.
“Over the intervening weeks our whole school community has been in shock and devastated by the tragic deaths of the children and their lovely mum.
“Ellie and Oscar’s friends and teachers will miss them greatly, Ellie was a selfless, generous young girl who was a wonderful pupil and friend.
“She was passionate about her learning, especially for PE, and she was always willing to help her teachers and peers.”
The statement added: “Oscar was an absolute treasure, always smiling and a friend to all.
“He was a wonderful role model and was nominated as ‘Boy of the Year’ for his kindness, resilience and always doing his best in everything.”
The funeral of Shirley, Ellie and Oscar was held on Friday, October 22 at Rotherham Minster.
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