Jadach volunteered with the Sparta Fire Department Ladies Auxiliary and was a treasurer for the Congenital Heart Defect coalition, her obituary reads.
Her brother, Christopher, said on social media that she had heart surgery when she was a toddler and recently beat breast cancer.
His tribute went on to say Monica was the "voice of reason" despite being seven years his junior.
"Monica was an absolutely amazing and SELFLESS individual who dedicated her time to the CHD Coalition as our Treasurer," the organization said. "She would never hesitate to volunteer her time to help with events and to serve the CHD Community.
"Monica was always positive and never asked for anything in return."
She is survived by her parents, Bozena and Krzysztof, her brother, Christopher and her dog, Heidi, according to her obituary.
A funeral was held on Tuesday, Jan. 9 at 11 a.m. at Our Lady of the Lake Church.
To view her obituary, click here.
Editor's note: A previous headline on this story inaccurately stated Monica was a Sparta firefighter. The headline has since been updated as Monica was a volunteer with the Sparta Fire Department Ladies Auxiliary, when she was an auxiliary member.
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