Matilda (Tilli) Friedrich (formerly known as Tilli de Boor) passed away on December 7th, 2025, after a brief illness, in Arlington, Virginia. Tilli was born on May 8th, 1938, in Locarno, Switzerland, far from her parent’s home in Cambridge, Massachusetts, but a place where her mother, Lenore, could give birth naturally, an experience she wrote about in an article in The Atlantic Monthly, called "I had a Baby." A photo of her future husband, Carl de Boor, was in the room where her mother recovered from the birth, because Tilli’s father was Carl’s godfather, a complicated story that the family enjoys trying to explain.

Tilli was the fourth of five children born to Carl Friedrich and Lenore Pelham Friedrich.. She was a graduate of Buckingham School and Radcliffe College, where she studied German Literature. She met Carl when she was visiting Germany in her senior year of high school, and he was asked to show her around. He said he fell in love with her eyes and the two exchanged letters until Carl came to America in 1959. They were married in 1960 and had four children together: Thomas, Lisa/Liesel, Peter, and Adam. They lived in great Midwestern university towns including Ann Arbor, Michigan, and Madison, Wisconsin, where Tilli went back to school to get a Master of Social Work degree. It was while working as a social worker in a nursing home in Madison that Tilli met Marilyn Howe, her partner for 14 years. Disappointed by the impact of funding on the scope of social work, Tilli went back to school and obtained a Masters in Public Administration, and worked in Wisconsin state government until she retired early in 2000, due to the objectionable impact of Republican Governor Tommy Thompson’s approach to government.

She moved back to Massachusetts in 2005, to live closer to three of her children, and then to Arlington, Virginia, in 2021, where she cherished the care of her son Peter and his wife Geneva.

An avid reader who easily devoured multiple books a week, she participated in many book groups where she enjoyed strong debates about writing. Tilli sang Alto at Radcliffe and continued to sing in choirs into her 80’s. In her later years, she also sought stronger spiritual ties to her community and converted to Judaism in 2011.

She believed strongly in democracy and the power of government to make a positive difference in our lives. She volunteered for many political campaigns, often embracing long shots who represented politics as she believed it should be, who often shocked the world in the process, including former ‘60's radical Paul Soglin's 1973 bid to become mayor of Madison, WI, Jimmy Carter's ascension to the presidency (when he was still known as “Jimmy who?”), Republican Congressman John Anderson's quest for the Republican nomination, followed by his independent presidential bid (in which he led or was neck-and-neck until late in the race), Rep Harold Washington's campaign to become the first Black mayor of Chicago, and DNR chief Anthony Earl's successful run for Wisconsin governor, which brought her into state government. In retirement, she continued to back the likes of Beto O'Rourke. Kamala Harris, and Pete Buttigieg, while encouraging and inspiring her children and grandchildren to get involved as well.

Her house was filled with needlework she created, CDs and albums of Baroque music she loved to listen to, and, for the last forty years, at least one dog. Over the years, she avidly supported, with time and money, a wide variety of organizations dedicated to the welfare of all creatures, great and small. Until she was no longer able, she also delivered food for Meals On Wheels.

Tilli is survived by her children Thomas de Boor (Gretchen Hermes), Liesel de Boor (Sheila Siragusa), Peter de Boor (Geneva Moores), Adam de Boor (Mari Osuna), her four grandchildren Corwin de Zahr (Monique de Zahr), Noah de Boor, Jasper de Boor, and Malva de Boor, and her great grandchild Gideon de Zahr. A memorial service will be held in the Spring of 2026 in Concord, MA.

In lieu of flowers, please consider donating to organizations that care for animals and/or support democracy.