The paper focuses on the life story of Celina Michałowska, daughter of the famous painter Piotr Michałowski. In 1868 she entered the Convent of Sisters of Immaculate Conception, whose cofounder, Sister Marcelina Darowska, had chosen Jazłowiec in Podolia as its principal seat. Celina, having adopted the name of Maria Celina of the Holy Trinity, spent half a century in Ukraine, serving the convent with her artistic talent. She developed the painting skills in her pupils, taught aetshetics as well as English, worked on translations and developed her own painting talent. In the convent workshop she painted pictures which later adorned other houses of the convent, chapels, churches and Uniate churches in Podolia. The present paper is aimed to shed a new light on the person of Celina Michałowska with the use of her unpublished correspondence with Blessed Marcelina Darowska.