Ocean Beach 05

John Leonard Brennan

May 9, 1962 ~ October 3, 2022 (age 60)


John Leonard Brennan, of Tierra Verde, Florida and Burr Ridge, Illinois, passed away unexpectedly on Monday, October 3, 2022, at the age of 60. John was born May 9, 1962, in Elmhurst, Illinois to Edward and Lois Brennan of Burr Ridge, Illinois. 

John is remembered for his innate ability to connect with others, remarkable kindness, faith, and humility, unwavering commitment to his community, and deep love for his family and friends. John left every room a brighter place and every person a better version of themself. Many knew John as an inspiring leader, a committed colleague, and a loyal friend, but his favorite role in life was loving husband, father, and grandfather. John’s presence can be felt from miles away and his impact will, simply, last a lifetime.

John had an impressive professional career. In his most recent years, during his “pseudo-retirement,” John directed his attention to his passion for real estate, as both a commercial and residential investor.

From 2007 until 2018, John led Private Wealth Management for William Blair & Company (Barron's Top 40 Wealth Managers) - notably leading growth of over $10 billion in just 4 years. Prior to, John was President of Bank of America - Illinois and Central US, Regional President of Bank of America Private Bank with additional executive level leadership positions at BofA spanning over 22 years - including marketing, corporate strategy, and commercial banking.

John showcased his commitment to the Chicago community through an extensive list of external engagements including Lead Director at a multi-billion dollar family office, Miami Corporation, Vice Chair of PBS affiliate WTTW/WFMT, Trustee and Executive Committee Member of DePaul University, Trustee and Chair of Quality Care Committee for Rush University Medical Center, Trustee for the Harris Theatre, former Vice Chair and Life Trustee for Chicago Public Library Foundation, and appointed by the late Cardinal Francis George as one of his key financial advisors, among a host of other community activities.                             

John is survived by his beloved wife Jean née. McLellan of 31 years and two children, daughter Kelly (Geoff)Powell; son Jack Brennan, and grandson Kane Powell. He is also survived by two sisters, Cindy (John)Walls  and Sharon Lisnow, two brothers, Ed (Debbie)Brennan and Don (Kim)Brennan , and two sisters-in-law, Babs (Jeff)Herman  and Karan (Andy)Stockett as well as numerous nephews and nieces whom he loved very much. John is preceded in death by his mother Lois Lyon Brennan and father Edward Allan Brennan, mother-in-law Barbara Brady McLellan and father-in-law John Kane McLellan, sister Linda Thode, nephews Marshall Brennan and Michael Lisnow, and niece Amy Lisnow.

A visitation will be held on Tuesday, October 11, from 3-7 PM at Adolf Funeral Home, 7000 S. Madison St., Willowbrook, IL. Family and friends will meet on Wednesday, October 12, for a 9:30 AM Funeral Mass at Old St. Patrick’s Church, 700 W. Adams St., Chicago. A private family interment will be held at Bronswood Cemetery, Oak Brook, IL.

In lieu of flowers, the family has asked that donations be made to the Michael Carter Lisnow Respite Center, 112 Main Street, Hopkinton, MA 01748.

To send flowers to the family or plant a tree in memory of John Leonard Brennan, please visit our floral store.


October 11, 2022

3:00 PM to 7:00 PM
7000 S. Madison St. Willowbrook, IL 60527
7000 S Madison St.
Willowbrook, Illinois 60527

Funeral Mass
October 12, 2022

9:30 AM
Old St. Patrick's Catholic Church
700 W Adams
Chicago, IL 60661

Private Interment

Bronswood Cemetery
3805 Madison St
Oak Brook, IL

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