The Alberta Court of Appeal has extended the sentence of 24-year-old Chad Mitchell Olsen.
Olsen was convicted earlier this year of slamming his pickup truck into the car of Brad and Krista Howe of Red Deer in February 2010.
He was originally sentenced to two years and three months, but the Appeal Court increased that to 3 1/2 years after a hearing in Calgary.
A five-year driving ban after Olsen gets out of prison remains.
Court heard he had a blood alcohol content more than three times the legal limit when he sped through a red light at 85 kilometres an hour.
Brad and Krista Howe, who were 34 and 35, respectively, died at the scene.
Sandra Green said she's happy with the increased sentence but nothing can replace her daughter and son-in-law.
"It's closer to what would be deemed as justice, but for me there is nothing that can replace what has been taken...whatever happens to him our position remains the same. We're without Brad and Krista, that's never going to change, no matter what."
Green said her other daughter is caring for the Howes' children, who she says are doing OK.
"They show signs of some insecurities when we're leaving but basically, on the whole they're doing extremely well, and they're functioning and playing and they're happy," Green said outside court Tuesday.
Olsen, who is from Sedalia, Alta., had nine previous speeding convictions and seven other traffic violations, which had already earned him three separate driving suspensions.
His original sentence sparked a public outcry from people who called for a stiffer sentence.