Mary Lu O'Brien, 97, of Decorah, died early Monday morning, May 12, 2014, at the Wellington Place Nursing Home in Decorah.

She was born July 10, 1916, the daughter of Terrance and Ellen "Nellie" (Sexton) O'Brien in Bluffton Township, Winneshiek County, Iowa. She was the fifth of seven children. She graduated from Bluffton elementary schools and Decorah High School. She was later awarded a bachelor's degree by Marycrest College in Davenport, Iowa.

After working in defense plants in Illinois and New Jersey during World War II, she became an educator. She taught the early grades in elementary schools in and around Rock Island, Ill., for approximately 30 years. She was a talented, devoted and successful teacher of young children. She retired from teaching in the Rock Island area and returned to Decorah to live in 1978. She lived in the Ludeking-Bruening and Noble apartments on the West Side until 2009, when she moved permanently to Wellington Place in Freeport, where she resided at the time of her death.

She loved to play euchre with her family and go dancing in her early years. In her retirement years, she volunteered at St. Benedict Catholic School, helping with art work. She was a member of St. Benedict Catholic Church in Decorah, and a friend of the parish in which she was raised, St. Bridget in Bluffton.

Although she did not have children of her own, she was an important aunt to 14 nephews and nieces. She is survived by her her sister, Lucille's family, Katie Kelly of Decorah, Martha Borek of Seattle, Wash., Terry (Alice) Kelly of Denver, Colo.; her sister, Rose Breitsprecher's two sons, Tom (Suzie) of Brandon, Fla., and Tim (Jeannie) of Mabel; her sister, Helen Carolan's family, Raymond Carolan of Seattle, Wash., Rosalyn (Keith) Bell of Tallahassee, Fla., Ruth (Louie) Orwitz of Rock Island, Ill., Eunice (Vince) McGuire of Rockford, Ill., and Mary Ellen (Richard) Kuhlman of Darien, Ill.; along with several great-nieces and great-nephews.

She was preceded in death by her parents; six siblings, Lucille (Bill) Kelly, Helen (Raymond) Carolan, Rose (Henry) Breitsprecher, Paul O'Brien, James O'Brien and John O'Brien; and nephews, Gene Kelly, David Kelly, Charles Carolan, Dennis Breitsprecher and Daniel Breitsprecher.

A Mass of Christian Burial was held at St. Benedict Catholic Church in Decorah on Friday, May 16. The Rev. Phil Gibbs officiated. Interment was in St. Bridget's Catholic Cemetery in Bluffton.

Arrangements were by Schluter-Balik Funeral Home in Decorah.