Dorothy A. Costa (Morrissey), of Somerville, passed away on January 20, 2026, at the age of 100. She was the beloved wife of 60 years to the late James J. Costa. Dorothy was a loving mother to Ruth Elio and her husband Daniel of Winchester, James J. Costa, Jr. of Somerville, and Martha Costa of Somerville. She was a cherished grandmother to Daniel and Matthew Elio, Jennifer, Michelle, and Amanda Costa, and a great-grandmother to Brady, Connor, Kate, and Brennan.

Dorothy was an active member of St. Joseph's women's Sodality and the American Legion Auxiliary, post # 377 in Somerville. Visiting hours will be held for Dorothy at St. Joseph Church, 262 Washington St. Somerville, on Wednesday morning, January 28, 2026, from 10:00 to 11:00, followed by her Funeral Mass at 11:00. Relatives and friends are invited to attend. Interment will be at Mt. Pleasant Cemetery, Arlington.