July 16 is the 150th anniversary of the death of Mother Thérèse Rondeau, the founder of the Congregation of the Sisters of Our Lady of Mercy in France (Laval), and co-founder of the Congregation of Our Lady of Mercy in Poland. She was born on October 6, 1793 in Laval, France. She was christened Theresa Agatha. Under the influence of her confessor, Fr. J. Chanon, S.J., Theresa undertook working with penitent women, that is to say women in need of deep moral renewal and willing to change their lives. In order to prepare better for this work, in 1818 she moved to Bordeaux, where Mother Teresa de Lamourous ran a house for penitent women, which was called “Mercy”. After a two-month stay, Theresa Rondeau made private vows and returned to Laval to become the foundress of a new work, independent from Bordeaux, and in time this became the Congregation of the Sisters of Our Lady of Mercy in France. Mother Teresa Potocka, née Ewa Sułkowska, who later became the foundress of the Congregation of the Sisters of Our Lady of Mercy in Poland, adopted the spirituality of the French Congregation and their way of conducting apostolic work. Mother Teresa Rondeau died on 16 July 1866 and was buried within the grounds of the Congregation in Laval; her tomb is in a garden belonging to the convent. Congregation of the Sisters of Our Lady of Mercy in Poland has named a co-founder. The spiritual co-founder of the Congregation is St. Faustina Kowalska.