Jack O'Brien

John "Jack" O'Brien, (54), of Glen Ellyn, Illinois, entered peacefully into eternal life on Sunday, June 8, 2025, on the Feast of Pentecost.

Beloved husband of Anna "Ania" O'Brien (nee Krempa), devoted son of Ronald and Patricia O'Brien and son-in-law of Marian Krempa and the late Stanislawa Krempa, loving brother of Kerry O'Brien (Doug King) and Mary Plunkett (Mark) and brother-in-law of Mariusz Krempa (Sylwia), and cherished uncle of Molly Klein (Garrett), Ryan Plunkett (Mary Beth), Tori Langella (David), Kelton Zimmerman (Megan), Callie Wernet (Daniel), Pawel Krempa, Natalia Krempa and Kinga Krempa.

Jack was a man of deep faith and strong conviction. He also had a brilliant mind and a wonderful sense of humor. He was a priceless treasure to his family and friends.

He graduated from Benet Academy in Lisle, in 1988, where he excelled in academics, music and track and field. He obtained his bachelor's degree from the University of Illinois in Champaign in 1992. He was the lead singer of a rock and roll band. He was Senior Manager at TEM Environmental, where he worked loyally for many years, gaining the respect and friendship of his team. He met the love of his life, Ania Krempa, and they married on February 4, 2017, at Holy Trinity Catholic Church Kosciól Trójcy Swietej in Chicago. Their marriage was a blessing to so many. He enjoyed nothing more than spending time with his family, especially during special trips to Door County, Wisconsin.

Jack was a parishioner at St. Petronille in Glen Ellyn, and also frequently attended Mass at Sts. Peter and Paul in Naperville, Holy Trinity in Chicago, and St. Mary in West Chicago. He was a member of the Knights of Columbus.

Requiem Mass will be celebrated at 11am on Saturday June 21, at Sts. Peter and Paul Catholic Church in Naperville, by Fr. Michael Magiera. Burial will be in St. Michael's Cemetery in Wheaton. There will be a prayer service at Williams-Kampp Funeral Home in Wheaton on Friday, June 20, from 3-4pm followed by a visitation from 4-8pm. In lieu of flowers, memorials may be made to Priestly Fraternity of St. Peter. You may also request a Mass intention or memorial Mass for the repose of Jack's soul.

Eternal rest grant unto him, O Lord, and let perpetual light shine upon him.