They were mother and daughter Maricel Martinez, 47, and Angelina Cardona, 12, said Saint Albert the Great Catholic School of Huntingdon Valley in a statement.
"Our Hearts are broken as we try to cope with the loss of our wonderful teacher and friend as well as her sweet daughter, a student in our 5th grade," administrators wrote.
"Mrs. Martinez, we will always remember your kindness and confidence exhibited in your classroom each day. Angelina, we will always remember the teacher compliments that you gave at the end of class and how sweet you were to your classmates."
A coworker identified the third victim to CBS Philadelphia as 56-year-old Jorge Cardona, Martinez's husband and Angelina's father.
The three were the subjects of a welfare check in Holmesburg on Thursday, Feb. 15, Daily Voice reported.
Police arrived at the family home on the 4000 block of Ashburner Street to find all three dead, the department said. Carbon monoxide was "suspected as the cause of death," but the official causes and manners of death are pending, authorities said.
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