"They're sitting there eating lunch before the game, looking at the field and the next thing she's on the floor," Maureen's mother, Margaret Oleskiewicz, told the paper. "He didn't even know she was in distress, and then she's on the floor.”
Margaret Oleskiewicz also told the Sun-Times that her daughter went into cardiac arrest and never recovered despite efforts to revive her.
"I think it happened about 1:00, it was just before the game started. Matter of fact, I remembered seeing them give her CPR while the National Anthem was playing," eyewitness Brent Olson said in an email to the newspaper.
"You could see everyone rushing up to the top of the seating with a frantic look on their face. They performed CPR like I've never seen," he said.
The Cubs released a statement.
"The Chicago Cubs are saddened to hear news of the untimely death of Maureen Oleskiewicz. We express our deepest sympathy to her family and friends. We will continue to keep her family in our thoughts and prayers during this difficult time," the statement said.
Maureen Oleskiewicz was kept alive until Tuesday, so her organs could be harvested. The newspaper reported her heart would be given to a 14-year-old.
Maureen Oleskiewicz's mother told the Sun-Times she had a knack for connecting with kids going through turmoil and that one of her lesson plans even incorporated rap, which was her students' music of choice.
"The kids got up and were dancing and rapping with her. Every kid got a good grade on that test," Margaret Oleskiewicz told the Sun-Times while reportedly choking back tears. "Maureen would make learning fun."
"There is no magic wand to fix what we cannot comprehend," District 128 Supt. Kathleen Casey wrote in a letter to parents. "Maureen had a positive impact on countless students, parents and ... colleagues. Her vibrant, positive outlook on life and her joyful nature will be missed more than words can convey."
The Incarnation Catholic Parish in Palos Heights was filled to capacity for a Tuesday night vigil, and students lit candles and laid flowers outside her classroom at an impromptu memorial afterwards, according to the Sun-Times.
"Even in death, she was so kind and good," Margaret Oleskiewicz said.