It happened just after 5 p.m. Friday, Sept. 25 in Farmingville.
Erika Bautista, 31, of Farmingville, and her three daughters were inside a northbound 2015 Honda, which had become disabled in the right lane of County Route 83, north of South Bicycle Path, Suffolk County Police said.
The car was then struck in the rear by a 2018 Jeep being driven by Chris Montpetit, 36, of Shirley, according to police.
Bautista and her daughters, ages 4 and 8, were transported to Stony Brook University Hospital for treatment of serious physical injuries.
Another daughter, age 10, was transported to the same hospital for treatment of non-life-threatening injuries.
Both vehicles were impounded for safety checks.
Montpetit was arrested at the scene for driving while intoxicated.
He is being held overnight at the Sixth Precinct and is scheduled for arraignment at First District Court in Central Islip on Saturday, Sept. 26.
The investigation is continuing and detectives are asking anyone with information on this crash to call the Major Case Unit at 631-852-6553.
All calls will be kept confidential.
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