According to police, 16-year-old twins Brittany and Tiffany Coffland were killed at the hands of their own father last Friday evening.
After shooting his two daughters, investigators say the girls' father shot his wife in the legs before taking his own life. The girls' mother was the only survivor.
"She was just a joy to work with. Everybody loved her there," one of Brittany's friends told WGN-TV outside of a visitation service for the twins.
Days later, 18-year-old junior Kody Dietrich was found dead with his girlfriend, 18-year-old Adalina Donoso. An employee at a nearby restaurant called police after seeing the two teens naked in the back of a parked car.
"We've been really upset about it," a St. Charles East High School student said.
The school has provided grief counseling services and therapy dogs for students and faculty in the wake of the two tragedies.
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