Judge Katie Cook Rayburn came to that conclusion following an hour of heart-breaking testimony from the family of the 2-year boy who died in 2018 after Casey failed to look both ways and pulled into traffic, causing a catastrophic chain of events that led to his death.
"There is no perfect sentence," Rayburn said before she announced her verdict. She said she tried to thread the needle between what was fair, legal, and just.
Along with the time in prison, Casey must serve two years probation, perform 100 hours of community service, and lose her license for 15 years, judge Rayburn ruled.
Colin's family wanted longer. His mother Kerri asked that the judge sentence Casey to at least three months in prison.
"He was the largest ray of sunshine imaginable," she said of her son. "A boy so full of life, he could walk into a room and steal all the attention with just a laugh.”
Kerri McGrath walked the court through the four years of torment her family has struggled through since Casey accelerated through the intersection of East 6th and L Street and clipped a van, sending it veering into Colin's stroller, his nanny, and his older sister Sloane.
"My husband and I are shells of ourselves," Kerri testified. "We've struggled with depression, insomnia, PTSD. We spend every Sunday at a cemetery instead of a soccer field."
Colin's father, Brendan McGrath, said little, preferring to read a letter from their daughter, who suffered five broken bones in the wreck.
"You ruined everything," he read from Sloane's note to Casey. "I’m not going to forgive you until you say you’re sorry. …. Sincerely, the very mad Sloane M."
Judge Rayburn said it would be unfair to say that Casey has shown no remorse for the wreck, as defense attorneys often instruct their clients not to reach out to the victim's family. She also noted Casey's tears as Colin's family spoke.
Kerri McGrath thanked South Boston for rallying around her family through the trial in her closing remarks.
"Because of our South Boston community, we are never alone," she said, "and Colin’s legacy will live on forever."
Click here to follow Daily Voice Dorchester and receive free news updates.