Newton - Berton Sumner Fliegel, a social worker and activist from Newton who devoted his career to fighting on behalf of the poor, died April 17, 2020 at the Belmont Manor nursing home from complications related to coronavirus. He was 90 years old.Fliegel is survived by his wife Susan, his son Joshua who lives in Seattle, daughters Lisa of Jamaica Plain and Janie (Fliegel) Howland of South Natick, and three grandchildren. His daughter, Dina Fliegel-Bocian, died in 1989.Alongside his wife, son and daughters, Fliegel is also survived by his sons-in-law Brian Howland and Arthur Bocian, and brother-in-law Louis Tanzer of Beverly. Fliegel had three beloved grandchildren: Russell Bocian, Davis Howland and Julian Howland. He was predeceased by his sister Roslyn Fliegel Tanzer of Beverly and brother Dr. Norris Eli Fliegel, who lived in New York City.A private graveside funeral will be held on Friday, April 17 at 1 p.m. A virtual shiva will follow.In lieu of flowers, donations can be made in his memory to the Hebrew Immigrant Aid Society at www.hias.org. Checks can be sent to: HIAS, P.O. Box 97077, Washington, DC 20090-7077.Levine Chapels, Brookline, 617-277-8300www.levinechapel.com